■".■'•; ' '..-i LIBRARY OF CONGRESS. Chap, Copyright No Shelf...... UNITED STATES OF AMERICA. ±~- ',...' PRACTICAL POINTS FOR Stationary, Locomotive and marine Engineers, Firemen, Electricians, piotounen and machinists. (ILLUSTRATED.) REVISED AND ENLARGED EDITION / BY JOHN S. FARNUM, M. E. TWENTIETH THOUSAND. PUBLISHED BY MECHANICS' SUPPLY COMPANY Chicago, III. Copyright, 1894, by John S. Farnum. Copyright, 1895, by John S. Farnum. Copyright, 1899, by WALTER G. KRAFT. PUBLISHERS' NOTICE. -ny^-n 59058 .v\ During the past few years the question of licensing engineers has been agitated in every part of the United States and Canada. A number of states have already enacted such legislation as to compel all kinds of engineers to procure a State License, others have provided for munici- palities to pass ordinances bearing on the subject, while still others are to-day seriously considering the matter. The result is bound to be, that in a short time, for the protection of life and prop- erty, no man will be allowed to run an engine without first going before a Competent Board and passing an examination whereupon a license will be issued to the applicant. This work is designed not to make an engineer of a man but to aid the proper persons to pass the required examination, whether it be for City, State or Government license. X foN j£ MECHANICS' SUPPLY CO. <7+ Irs * i ' 1 0- HO *p4 TWO COP 1SS R ECE1VE£J 0ff *eo of ffc , ^281000 SECOND COPY, 0g " ,er ° inBB** *¥"'?' *?? PAGE. Boilers, construction 5 Boilers, management 17 Boilers, incrustation etc.. 23 Firing, stationary 27 Firing, locomotive 35 Safety valve 31 Steam 42 Water 45 Injectors and pumps 49 Combustion 57 Steam engine 62 Lubricator 68 Steel square 71 Valve motion 75 .Locomotive valve setting. 75 Horse power 78, 88 Indicator 81 Locomotive break downs . 89 Air brake 105 Speeding and signals 125 Engine whistles 128 Signals, train 129 Signals, torpedo 130 Semaphores, etc 131 Mixed questions, etc 132 Rules and recipes 137 Rules to polish boilerheads etc 138 Rules to cool hot pins 138 page. Rules calendar calcula- tions , . . . 138 Rules to clean brass 139 Rulesto cover boilers, etc. 140 Rules for steam heating 141, 163 Brick work for boiler beds etc 143 Engine foundations 145 Melting, boiling and freez- ing points 146 How sound travels 147 Tempering 149 Row to draw an ellipse . . . 150 Role to find circumfer- ences 153 Weights and measures 154 Properties of saturated steam.. 155 Area of circles 156 To mix colors, etc 157 Corliss engine 165 Automatic engine 167 Automatic governor 167 Electricity 168 Dynamo 171 Motors 179 Telegraph and Batteries . . 189 Telegraph sounder 192 ILLUSTRATIONS. j»AGE. Duplex Pump 50 Injector 52 Indicator 81 Slide valve automatic en- gine 64 Steel square 71 Indicator diagrams 82, 83 Ellipse 151 Diagram to erect a perpen- dicular line 152 Corl^s engine 165 PAGE. Automatic engine 167 Dynamo 171 Skeleton dynamo 172 Arc lamp 173 Armature 174 Incandescent lamp 176 Arc dynamo 178 Electro motor 179 Telegraph key 190 Telegrapher's code 191 Sounder 19? PEEFACE. This edition has been thoroughly revised and enlarged so that now I believt it to be the most complete work of its size for sta- tionary, locomotive or manne t/igineers, firemen, etc. This work goes into the points deeper and explains them with the plainest of simple lan- guage, so that men of limited education can understand as well as a man of high education. We all know that the proper way for a man to learn is by practice. But the two, practice and theory together will make a man more per- fect. Reading of other mechanics' ideas will enable a man to better his own ideas and perform his work more perfectly. Those preparing for an examination and ex^ pecting to receive a license should by all means procure this book as its practical suggestions throughout, will enable them to get their license. The book treats on boilers, engines, firing, combustion, indicators, dynamos, motors, elec- tricity and has valuable receipts and rules. Trusting that my efforts in trying to please the general run of engineers will be appreciated by all. I am Respectfully yours, JOHN S. FARNUM. The following questions and answers are for loco- motive ', stationery and marine engineers and firemen to use as a guide in preparing themselves for an ex- amination. First you must fill out a blank and have same properly signed before going before the examin- ing board. Then await your turn and be ready when called. CONSTRUCTION OF BOILERS. Q. What is a steam boiler? A. A steam boiler is an air tight vessel and may be divided into three divisions or six classes, namely: locomotive, marine, tubular, flue, hanging fire box and upright boilers. The hanging fire box is fired inside of itself, tubular and flue boilers are fired externally having an attached furnace. Q. How are marine boilers fired? A. They are fired inside of themselves. Q. Are boilers single or double riveted? A. They are both. Single for low press- ure and double for high pressure. Q. Name the different strains the boiler has to contend with? A. Bursting strain and tearing. Q. Is the strain greater on the sides than on the ends? A. Yes. Q. Why so? 6 A. Because the steam pressure has a larger surface to work on. Q. How are boilers strengthened? A. They are strengthened by stay bolts and braces. Q. Name the different braces in general use? A. The stay bolts, the angle brace, crow- foot, side brace, longitudinal and dome brace. In hanging fire box boilers the crown sheet is braced by what is known as crown bars. Q. Of what construction is a successful and economical boiler? A. The chief points are in proper circu- lation facilities and good construction. For tubular boilers place the tubes in vertical rows leaving out centre row. The circula- tion in a boiler is up on the sides, down the centre. Ziz-zag tubes check the circulation and give poor results. Q. State the strain on a stay bolt and how is the calculation made? A. The stay bolts, as a rule, support an area of thirty-six square inches, multiply the area by the steam pressure and you will have the strain upon each stay bolt. The distance that stay bolts should be set apart should not exceed six thousand pounds per square inch cross sectional area. To determine the distance multiply the cross sectional area of bolt by 6,000, divide by steam pressure and extract square root of quotient. Q. State the surface of plate a stay bolt has to support? A. The support is represented by the rectangle or area enclosed between four bolts. Q. How is the rectangle known between four bolts, each six inches apart? A. It is known by multiplying one dis- tance by the other; 6x6=36 square inches, each bolt has to support. Q. Of what use is a hollow stay bolt? A. It is used to supply air above the fire and help combustion. Q. Compute the horse-power of a hori- zontal tubular boiler, 5 foot diameter, 16 foot long, containing 78 3 inch tubes, each tube 16 foot long? A. Multiply diameter of shell by 3.1416 to get circumference 15. 70 feet, the lower half of shell being the only heating sur- face divide this by 2 which equals 7.85, multiplied by the length of shell 16 feet equals 125.60 square feet. The circumfer- ence of 3 inch tube is, 9.42 inches by the 8 same rule multiplied by its length, 192 inches equals 1808.64; which multiplied by the number of tubes, 78, equals 141,073.92 square inches, or 979 square feet, which added to the square feet of the shell equals 1 107 square feet, divided by 15 equals 73^3 horse- power. Q. Name the number of square feet of heating surface allowed to a horse-power in different makes of boilers? A. Horizontal tubular boilers 15 square feet, vertical 12 square feet, locomotive 12 square feet, flue 10 square feet and plain cylinder 9 square feet. Q. How many square feet of grate sur- face does it take to consume 12 pounds of coal? A. One square foot. Q. How many pounds of water will be evaporated by one pound of good coal? A. The average will be 6 to 10 pounds of water. The average result is about 25 to 50 per cent, below this, for it is estimated by some of the best* authorities that 1-16 inch of scale in the boiler causes a waste of 10 to 15 per cent, of fuel and in this proportion upwards according to the thickness of scale. Q. How would you know the amount of water a boiler is evaporating by a given num- ber of lbs. of coal used in one hour, say 1,000 lfcs.? A. Simply divide 1,000 (or lbs of coal) by 7^, and answer will be cubic feet of water. Multiply ans. by 7%, and the result will be the number of gallons evaporated in one Mour. Q. How many gallons of water in one cubic foot, also how many cubic inches? A. There are 7^ gallons in a cubic foot f md 1728 cubic inches in a cubic foot. Q. Name some of the causes of boiler ex- plosions? A. Explosions of steam boilers are gen- erally due to defective material, defects of construction, improper management and natural causes. An explosion takes place when the resistance is less at some point than the pressure to which it is subjected, and may happen even when the pressure is very low. The explosion of a boiler is not an instantaneous action, although it seems 50. It is a well defined and rapidly succeed- ing series of operations. The rupture com- mences at a point where the resistance of- fered by the material is less than the strain to which it is subjected and it extends into 10 the adjoining part when these parts are too weak to sustain this increased strain that the rupture already made brings to bear on therr^ together with the shock due to the motion that the edges of the fracture make while seeking a new state of equilibrium. In case of an explosion the steam pressure does not fall the instant the rupture takes place ; on the contrary the pressure continues very nearly up to the time when all the water has escaped from the boiler. An explosion is so much more terrible as there are mor^ fractures made prior to the moment when the boiler is entirely emptied of its water. Q. Is it dangerous to let water run low in the boiler? A. Yes, it is very dangerous as the plates become red hot, and the softened plates will tear open and may produce an explosion if the hot part is hot enough or if the adjoining parts do not offer sufficient resistance. Q. Is the steam pressure lowered when feeding a boiler with low water? A. When water is fed into a boiler when the water is too low it almost invariably lowers the pressure of the steam. Q. Is it dangerous to force wrter into a low water boiler with a hot fire in the fur- nace? 11 A. Yes it is always dangerous to feed, before dampening the fire because the water injected quiets the ebullition and increases the surface exposed to the heat. Q. Is it dangerous to empty a boiler when the tubes or flues are still hot'/ A. Yes, it is dangerous; for such actions cause fractures of the transverse riveting in such manner as may not always be shown by leakage, and this effect may very easily pro- duce an explosion when next the fires are lighted or in a short time afterwards. Q. Why should a tubular boiler be kept clean on the outside? A. Because when a plate is covered with soot or incrustation most of the defects can- not be seen, therefore it is very important that boilers should be kept as clean as pos- sible externally as well as internally. Q. Name the various steps in an explo- sion which have heretofore been mentioned? A. First, a fracture in a plate followed by a rending; second, a violent bursting out of water and steam; third, a falling pressure; fourth, portions of the water are propelled with great violence against the shells of the boiler and shattering it by the expansive force of the steam disseminating throughout 12 the body of the water; fifth, the steam gen* erated from the liberated water imparts a high velocity to the fragments, converting them into projectiles, thus spreading ruin and destruction around. Q. From the various experiments and investigations what conclusions have been arrived at? A. A violent explosion may take place in a boiler when there is plenty of water in it; second, that a moderate pressure of steam may produce a terrific explosion when there is plenty of water; third, that a boiler may explode under steam at a less pressure than it has stood without apparent injury from a water pressure or hydraulic inspection, there- fore hammer test is the better; fourth, a rup- ture will be followed by relief of pressure with or without explosions as the fracture is extended or otherwise; fifth, that an explo- sion rarely occurs in an externally fired boiler from low water. Q, How is the safe working pressure of a boiler found? A. Multiply twice the thickness of the shell by the tensile strength, and divide the answer by five times the diameter of the shell in inches. 13 Q. State the proper place for a lowei gauge cock in a tubular or flue boiler? A. Two inches above the upper row of flues. Q. State the proper place for a lower gauge cock in an upright boiler? A. One-third the distance between the two flue sheets, measuring from the top flue sheet. Q. What is known as the fire line of a boiler (Tubular)? A. The fire line is between the water line and the top row of flues. Q. What is known as the water line? A. The water line is known as two inches above the flues. Q. What is corrosion? A. Corrosion is one of the strongest de- structive forces to which the boiler is sub- jected. Internal corrosion is caused by the concentrated acids of the water, which attack the most susceptible portions of the plates or tubes, and if the acids are volatile or the liquid acids carried by foaming or priming into the steam space, the plates there also suffer. Corrosion is very capricious in its action, some boilers are attacked on the shell, others will suffer principally in the 14 tubes, and others at the rivets and seams. The erratic action must be ascribed to the gravity of the acids at work, their concen- tration in certain parts due to the circulation of the water, to the nature of the iron or steel, and to other causes more obscure. Uniform corrosion is that species of the wasting of plates, tubes, etc, in a more or less even manner, and is like ordinary rust- ing in its character. Pitting or honey-comb- ing is another form, well marked by the sharply defined edges they present, and is. usually found in patches of various sizes. Q. What causes grooving or channeling? A. Grooving or channeling, as it is usu- ally termed, is due to the mechanical action produced by unequaled expansion and con- traction. Q. Where would be a good place to force in the feed water to overcome grooving? A. Introduce the feed water near the water level in the boiler instead of near the bottom, it will help some. Q. Would you consider it dangerous to empty a boiler when the tubes or flues are hot? A. Yes. Q. Is it dangerous to fire up a boiler too rapidly? 15 A. Yes, it is very dangerous, as where the draft and combustion are sufficient for a white heat, the plates, no matter how good they are, cannot resist with certainty. Q. Name over several kinds of explo- sions? A. Scaly boilers, by overheating, defec- tive circulation, corrosion, explosion of gas in the furnace of flues, hydraulic testing by straining, letting water run low and over- heating, then pumping cold water into the boiler. Q. What causes defective circulation? A. When boiler tubes are too close together and not having room enough for * he water to circulate when making steam. Q. How far apart should the tubes or flues be for proper circulation? A. They should be y 2 the diameter of the flue itself apart, and in perpendicularrows. Q. How is the tonage strain on the crown sheet of a fire-box known? A. Multiply the length by breadth in inches, divide by 12 for feet; multiply ans. by steam pressure and divide by 2,000. Ans. is tons. Q. State rule to find amount of strain a crown sheet will withstand? 16 A. Simply use same rule as above and divide the tonage by 2.66 if a ^ inch plate, \ if a % inch plate, and 2 if y 2 inch plate (thickness). 17 MANAGEMENT OP BOILERS. It is fully as important to manage a boiler properly as it is to have it properly designed and constructed. From the time the boiler is set at work it is subject to destroying forces which must he counteracted as much as possible. Therefore the person under whose immediate charge the boiler properly comes, should be a strictly sober and competent man. Q. What is the first duty of a fireman or en- gineer before starting a fire under a boiler ? A. He should see that there is plenty of water in the boiler by trying the guage cocks. Q. What next should he look after f A. He should see that the blow-off cock is shut, that the hand-hole and the man-hole plates do not leak, or if they do he must tighten them with wrench and hammer ; also look at seams and tube or flue ends for leaks. Q. If circumstances will allow how should a boiler be cleaned ? A, When the fire is hauled, the throttle valve on the steam pipe next to the boiler should be shut; the ashes and cinders quenched and wheeled to the ash pile ; the furnace and ash pit doors and the dampers should be closed, and the steam 2 18 blown off at the safety valve until there is only about five pounds pressure ; then the safety valve should be lowered to its seat. Q. Would you blow out the boiler then? A. No, let the water remain in the boiler until it and the furnace is cool, then let the water and slush run out through the blow-off cock. Q. Why not blow out water with a light pressure on? A. It has a tendency to weaken the seams and also the boiler in general, by uneven expansion. Q. What is next done after boiler is empty? A. When the boiler is empty, the man-holes and hand-holes may be opened, and the boiler rinsed out; then examine carefully inside; the scales must be knocked off with light blows of a pick or scraped with bars and chisels, or loosened with angular wire chains, etc., then wash the boiler clean with water. Q. When should the scale be removed? A. The scale should be removed &s soon as possible after the water has been let out of the boiler, before it has time to dry and harden, if any repairs are to be made to the braces, etc., they should be made and the boiler closed up. Q. How about the outside and connections of boiler ? A. The flues and connections should be swept 19 and the boiler bottom scraped with a wire brushc After above the boiler is ready for filling with water, which should be done at once, and then it should be examined carefully for leaks, which if found should be repaired at once, before the boiler is put into use again, if, however, it is not intended to use the boiler for some time it will be well to drain all the water out of it, and to dry it thoroughly by pans of charcoal, and then set a pan or two of lime into the boiler, and close it tightly. Q. Why dry the boiler and set in it pans of lime and close it tight ? A. To prevent oxidation. Q. Name the principle tools about a fire room or boiler room? A. A full set of tools consist of a shovel, slicebar, T bar pricker, hoe, coal hammer and devils claw, together with a broom and dust brush, and also a chipping hammer, a flat cape and diamond point chissel, and wrenches to fit the nuts and bolts about the boiler, a monkey- wrench and screw driver. Q. State the tensile strength of a boiler tube, say three or four inches in diameter, or how is the strength of the tube calculated longitudi- nally ? A. The standard thickness of a three inch 20 tube is .109 of an inch ; its circumference is 9.4248 inches. There would have to be pulled apart 9.4248 x. 109 = 1 0273 square inches of iron to separate the tube lengthwise. One square inch will hold from 40,000 to 50,000 pounds. As- suming 45,000 pounds as the tensile stength pet square inch of section, it would require 45,000 x 1.0273 = 46,288 pounds to pull the tube apart longitudinally. Q. What pressure will a tube resist when expanded into the headsheet of a boiler beaded, and not beaded ? A. The Hartford Steam Boiler Inspection and Insurance Co, prepared and had tested three inch tubes expanded into plates with a Dugeon expander, without beading. The first was expanded into a 3-8 inch plate, and it re- quired 6,500 pounds to pull it out. The two others were expanded into 15-32 inch plates, and it required 5,000 and 7,500 pounds respec- tively to pull them out They later prepared two similar specimens, both tubes left projecting beyond the tube sheet and flared and expanded into 3-8 inch plates. The observed stress which first produced yielding was 20,500^ pounds in one and 19,000 pounds in the other, 500 pounds additional being required in both cases to com- pletely dislodge the tubes. 21 Q. When calculating the load on a safety ^alve, is any allowance made for atmospheric pressure on the back of it ; if not, why ? A. No, because the gauge pressure in which the results are figured and expressed signify the difference between boiler pressure and atmos- pheric pressure, not the absolute pressure in the boiler. There must be atmospheric pressure in the boiler when the pointer stands at zero, and one pound above the atmosphere, or 15.7 abso- lute, when the gauge indicates one pound. Q. How much hydraulic test should a boiler be put to, to carry 100 pounds pressure of steam? A. It is usual to subject a boiler to hydraulic pressure 50 per cent, greater than the steam which it is to carry. For 100 pounds pressure of steam, the hydraulic test should be 150 pounds. Q. Is the hydraulic test for boiler the better way to test a boiler ? A. No, the hammer test is the best. Q. Why is the hammer test the better of the two ? A. Because boilers can be strained by the hydraulic test and show no leak when the pres- sure is used, but when steam is raised the boiler expands and opens the strain caused by the cold water test 22 Q. Can you give a good short rule and ex- ample to figure a safety valve, and know at what pressure it will blow off ? A. Yes, after having taken all the measure- ments, length of lever fulcrum, weight of lever valve and stem, and weight of ball, we divide the fulcrum into the length of the lever, multiply by weight of ball, add the weight of lever valve and stem when connected at the fulcrum, and divide by the area of the valve. Example: lever twenty-four inches long, fulcrum four inches, weight of lever, valve and stem, 32 pounds ; diameter of valve 2^ inches = 3.9 area. Weight of ball 40 pounds, 4-^-24 = 6x40= 240 + 32 = 272 -s- 3.9 = 70 pounds steam pres- sure boiler will blow off. Q. Are spring pop valves figured? A. No, they are set with a guage, specially made for the purpose. Q. Of what use are safety pop valves? A. They are supposed to release the* boiler of all pressure above a point at which they are set. Q. State the proper size of a safety pop? A. As a rule three square feet of grate surface equals one square inch of pop valve (area). 23 BOILER INCRUSTATION AND CORROSION. The prevention of incrustation and corrosion is of vital importance. In fact, there is no sub- ject of so much importance in the promotion of the efficiency, economy and life of the steam boiler. Among the evil effects arising from the pres- ence of incrustation and corrosion can be directly attributed, a loss of fuel, varying from 1 to 37 per cent. If waste of fuel were the only evil incident to the mismanagement of steam boilers, it might be tolerated in localities where fuel is abundant and cheap; but other great evils result from in- crustation, such as burning of iron, granula- tion of the material, bagging, blistering, and fracture of the sheets, flues and tubes. Also pitting of iron, and many other forms of corro- sion. All of which having the tendency of des- troying the tensile strength, elasticity, and resis- tance of the iron, and rendering it liable to explosion at any time with disastrous effect. If the steam boiler is expected to render proper service,to be safe and durable, and an easy steam generator, certain conditions must be complied with. It must be intelligently managed, care- 24 fully fired, not over taxed, and above all, kept safe and clean on the inside. To properly protect the interior of the steam boiler, to keep the iron clean and in good safe condition, chemistry is undoubtedly the only source from which to seek relief and protection from the disastrous results occasioned from the above named destructive agents. The corrosive and destructive acids contained in solution in water, can only be neutralized by the interven- tion of a chemical basis, and it must be borne in mind than no mechanical means can fulfill this requirement. In consequence of the demand for an efficient and reliable preventative of incrustation and corrosion, a great variety of nostrums have been placed upon our market, and offered to steam users under attractive names, and for which ex- ceptional merit is claimed; but an analysis of these preparations, together with a knowledge of their components, and resulting actions, dissi- pates these claims and conclusively demonstrates that, with few exceptions, the manufacturers of the same have not the requisite knowledge of chemistry, that would entitle their preparations to the confidence of the steam user. The author has had a wide experience in the capacity of Boiler Inspector for many years, in 25 which experience he has come in contact with nearly all the steam users in several states, and during this experience, I may honestly affirm that I have found but one preparation which I consider entirely reliable as a remedy for incrus- tation and corrosion in steam boilers. This article has gained a world-wide reputa- tion, and is endorsed by the leading authorities not only thoughout the United States, but also in foreign countries, to which it is exported in large quantities. The article I refer to is man- ufactured in Philadelphia, Pa., by Mr. Geo. W. Lqrd, a practical manufacturing chemist and engineer, who is also w T ell known as an author and contributor to some of our best scientific works on steam engineering. His preparations are known as "Lord's Boiler Compound," but I will here state that the words " Lord's Boiler Compound " are only his trade mark, under which such different compounds are prepared, as each individual steam user may require; or such specific preparations as may be required, where the same or similar waters are used in certain territories, and Mr. Lord's ex- tensive trade is no doubt, due to his scientific knowledge and skill in furnishing a preparation, which is suited to the requirements of each indi- vidual case 26 You may have noticed circulars and other ad- vertisements of boiler cleansing preparations, which the manufacturers claim to be purely veg- etable. It is a well known fact that vegetable matter principally consists of acids, oarbon, earthy salts, etc., and the active and soluble properties contained in these preparations, are acids which are more harmful to the boiler than any boiler incrustation. Oil is also frequently employed as a prevent- ative of boiler incrustation, but any intelligent engineer will understand that this invariably induces overheating, and burning of the plates, tubes and flues. Oil has the property of penetrating the pores of boiler incrustation, and detaching it in large fragments from the boiler surfaces, thereby pre- cipitating this aggregate mass directly over the heating surface, causing burning, blistering, and bagging of the material. This is a dangerous practice, and one liable at all times to invite boiler explosions. Oil is also a convenient cloak, under which to introduce vegetable and mineral acids into the boiler, and this daring practice is of fre- quent occurence, and is worthy of criminal prose^ 1 * 1 '™ 27 PROPER FIRING. Firing is only done properly when the fuel is consumed in the best possible way, that is, when no more is burned than is necessary to produce the amount of steam required and to keep the pressure uniform. To reach this end complete combustion must be attained in the furnace, and to know when this is going on, is when the fuel is burning with a bright flame evenly all over the grate furnace. Q. How do the colors show when the fire is badly managed i A. Blue flames, dark spots and smoke, are the best evidence of incomplete combustion. Q. What is the cause of bad combustion? A. It is caused by not having air enough above the fuel in the furnace. Experience is the best teacher although points from a book are very applicable in all cases of firing differ- ent makes of boilers. Q. How should the tools be placed about a boiler room ? A. Every tool should have its place and be kept there when not in use, and if broken should be repaired at once. Never keep furnace doors open longer than absolutely necessary, and the firing should be done as quickly as possible. 28 Q. Why should the furnace door be closed quickly and the firing done quickly ? A. To prevent contraction of the boiler bot- tom from the cool air entering the furnace. Q. Should a fire be stirred often? A. No; the fire should not l3 stirred any more than is necessary. Q. Why? A. In order to avoid the waste from small coal from dropping through the bars. Q. Suppose the chimney draft was very strong, how could it be controlled ? A. Simply close the damper partially, also the ash pit doors. Q. Name the proper thickness of fires under boilers ? A. For anthracite coal, the thickness should be from six to eight inches generally. For bi- tuminous coal from eight to ten inches, and with coke from ten to twelve inches. Q, How large should the coal be when thrown into the furnace ? A. Not larger than a man's fist. Q. State the best way to start a fire under a ccld boiler ? A. Cover the grate bars with coal for about two-thirds of their length from the bridgewall, and should pile a little wood, cob-house fashion, 29 on the open bars, and put a few lighted shavings or oily waste in the mouth of the furnace, partly close the furnace doors, and wholly close the ash pit doors. Q, Why is coal thrown back on the grate bars first ? A. The coal on the grate bars prevents air from coming through them and impairing the draft, while the partial opening of the furnace door supplies air to the burning wood and directs the flame over the coal in the back end of the furnace, gradually heating the coal up to the point of ignition. Q. What is next .done ? A* After the wood is burning well, coal may be thrown upon it and the furnace doors closed the ash pit doors being then open. Q. When is more coal thrown in on the fire? A. As soon as the fire will bear it being done, and the fire is gradually pushed back until there is a full fire on the whole length of the grate bars. Q , Should a fire be hurried 7 A. No, it must be allowed to "come up" as it is termed, very gradually, and to do this put on a little coal at a time. Q. How should a fire be kept ? A. The fires should always be kept level and 30 of a uniform thickness, with the exception that at the sides, corners, and at the bridge wall it must be enough thicker to prevent cold air from leaking through. Q. When should a fire be cleaned? A. The fire should be cleaned when the clinkers and dirt accumulate to an extent suffi- cient to clog the draught. Q. How are the fires cleaned? A. Boilers with wide furnaces it is better, perhaps, to clean only one half at a time and let the fire burn up well on that side before attempt- ing to clean the other half. Q. Where there are several furnaces all lead- ing into the same chimney, how should they be fired? A. They should be fired alternately in order to keep the steam at a regular pressure and ob~ serve the greatest economy and fuel. Q. Is it a good idea to wet coal just before firing? A. No, it is wasteful of heat and produces corrosion. Q. Is it safe to close the damper entirely? A. Never close the damper entirely while there is fire on the grates as gas may collect in the flues and an explosion may take place which 31 would ruin the boiler ; it is also apt to " burn down" the grate bars. Q, Are there any reasons to believe that boilers have exploded through the explosion of gas? A. Yes, there are reasons to believe that boiler explosions have been produced in this manner. Q. Is it proper to bank a fire? A. Yes, a banked fire properly kept up is conducive to longevity of the boiler, because of the less amount of contraction and expansion induced owing to difference in temperature. Q. How should the feed- water be supplied? A. The feed-water should be supplied regu- larly and continuously and the water-line should be kept at a regular height, and there should never be less than three or four inches in depth over the highest part of the furnace, flues, or connections exposed to the flames or hot gases ; but it is very bad practice to carry the water too high in a boiler as it will cause priming. Q. Which is the proper way to try the safety- valve ? A. By raising steam until the boiler safety- valve begins to " simmer," noting the pressure by the steam gauge at the moment. Q. Can a safety-valve not be raised by hand? 32 A. Yes, but that would not inform me that it would blow off at the proper time with pro- per pressure. Steam pressure should never be allowed to exceed its highest blow-off limit. Q. Suppose the steam gauge was showing that the steam was rising rapidly what would you do? A. Simply feed water in the boiler at once, partly close the damper and the ash pit doors. If in spite of this the steam is still rising, open up the furnace doors a little, and feed more strongly. Q. Suppose the water rose in the glass higher than practicable, w T hat should be done? A. Open the blow-off a little, at the same time watch the water-line very closely, by con- tinuously trying the gauge cock. Q. Suppose the water was dangerously low when the steam started to raise would you pump in water? A. No ; if the pump is in motion at the time, leave it continue. The furnace doors must be opened and damp, small coal and ashes thrown over the fire, then in a few minutes the boiler will be cool enough to allow pumping up. In such a case examine the top row of flues for leaks. 33 Q. How often should the gauge glass be blown through during the day ? A. Several times every day, also the gauge cocks should be tried about every half hour. Q. Why try the gauge cocks when you know by the glass gauge you have water? A. To know if the glass is in working order. Q. What is "foaming"? A. Foaming is a violent mixing of the water and steam in the boiler which results in " prim- ing" or the carrying of the water, in the state of a fine spray, with the steam into the engine cylinder, often knocking out a cylinder-head, rapidly lowering the water-level in the boiler sometimes so much as to be dangerous. Q. What generally causes foaming? A. Foaming is generally caused by irregu- larity in firing or feeding, impure water, espe- cially if it be greasy ; contracted steam r >ace ; too small extent of area at the water-line ; from the tubes being crowded together; the boiler not being clean; the throttle or safety-valve being opened too suddenly ; the boiler not being clean, and in marine boilers changing the feed water from salt to fresh, or the reverse. Q. Explain how one can know when a boiler is foaming ? &.. It is generally shown in the glass gauge 34 by a sudden t^i'ng or falling of the water, or by boiling or showering of the water down through the glass, also by a peculiar sput- tering sound given upon opening the gauge cock. Q. How can it be overcome? A. It can be overcome by partially closing the throttle and opening the furnace doors and feeding strongly; sometimes, however, it is necessary to blow out a little water from the boiler, but this should not be resorted to except in extreme cases. Keep the boiler clean, and the water clean, and little of such trouble will occur. Q. How much pressure per square inch of steam should there be in a boiler before the needle on the steam gauge begins to move? A. About 15 pounds pressure per square inch. Q. Why? A. The atmospheric pressure in the boiler must be overcome. Q. By what power is a steam gauge needle moved; also state the use of the cir- cular bent pipe between boiler and gauge? A. The needle is moved by expansion of the condensed water left in the crooked pipe 35 under gauge. If it were a straight pipe and steam came in direct contact with the gauge it would sweat the glass and not show a true state of affairs. LOCOMOTIVE FIRING. Q. What is your understanding of steam pressure as shown by the steam gauge? A. The steam gauge shows the steam pressure on each square inch on the inside of the boiler. Q. What is the result on the exhaust steam going through the stack? A. It carries the air up through the stack with each exhaust and by drawing it from the front end produces a partial vacuum there. Q. In what way does the exhaust steam create draft on the fire? A. When the air is drawn out of the front end, the air and products of combus- tion in firebox flow through the flues to fill the space, this in turn allows the pressure of the atmosphere to force fresh air up through the grates and fire and makes a steady flow 01 an* into the firebox. Q. What is your idea of the proper siz( 36 of stack — inside diameter, length, ar,... \ k" hi Cn © B, fc3 ^M fc' *OI s ft \ *9_ \ Is* 83 h * & • k. \ r c z> 5 £ | J rr i s ? 3 m S* f* >> w / j / , Q y / / y / / / J t 1 t / ; ": m, f 84 sires to record the result of a series of ob- servations or experiments in such a manner that they may be at once be apparent and easily comprehended, he has recourse to what is known as the graphic method. Sup- pose, for instance, it was desired to repre- sent in this way the result of a series of observations of the temperature of feed water during the test; take a piece of paper ruled in squares as represented in figure i, page 59, which is known as ordinate paper, we set off the time upon one of the horizontal lines, as shown at the bottom of the figure, and allowing two spaces for each fifteen minutes to represent one degree of temper- ature, making the lines so figured to corres- pond to 175, 180 and 185 degrees. Now at ten o'clock the observations showed 176 degrees, so upon the line representing that time and at a height representing 176 we make a dot fifteen minutes later the temper- ature had gone up to 178 degrees and upon the line represented 10:15 an( i at a height representing 178 another dot is made. Con- tinuing in this way to represent the result of each observation and connecting the dots by lines we obtain a diagram showing at a glance how nearly regular the pressure was 85 maintained through the test, to what extent it varied, and at what time the variations occurred. Let us apply this method to the variation of pressure in the cylinder of a steam en- gine. Suppose we have an engine with a stroke of 48 inches, cutting off at % stroke, with steam at 60 pounds and a variation of 12 pounds. In figure 2, page 60, let the line o represent the pressure of the atmosphere; i.e., the zero pressure of a steam gauge, and set off upon it 48 spaces to correspond with the 48 inch stroke of the engine. Now, at the beginning of the stroke at A, steam is admitted, and calling each vertical division 3 pounds we set off 60 pounds upon the line A, B; this pressure is supposed to be main- tained for a quarter stroke, and thus for 12 of the horizontal divisions the pressure would be represented by the horizontal line B. C. At the point C the supply of steam to the cylinder is cut off and the pressure behind the receding piston falls by expan- sion. The pressure for any position of the piston can be easily calculated by a method which will be explained at the proper time. Placing upon the vertical lines representing each inch of the stroke a dot representing a 86 corresponding pressure and connecting these dots we have a curved line representing the variations of pressure during expansion, at the point D, two inches from the end of the stroke, the exhaust valves supposed to have opened for release, allowing the pressure to gradually fall along the line D, E, F, to that of the condenser, 12 pounds below the atmospheric line. This is the pressure which should be before the piston on its return movement up to the point G, four inches from the end of stroke where the exhaust valve is supposed to have closed for com- pression, and the pressure of the enclosed steam is raised along the curve G, A. Now, the steam engine indicator applied to this engine would produce a diagram more or less approaching this theoret- ical form, the pressure being measured by the vertical movement oi the indicator pis- ton and the piston movement of the engine by the movement of the paper drum which is directly derived from it, as heretofore described. It furnishes us with a graphic representation of the distribution of pressure in that end of the engine cylinder to which it is attached for a complete revolution. By its means we are able to see at once whether 87 the various operations occur on time with reference to the piston movement, how nearly the boiler pressure is realized in the cylinder; at what point it is cut off and how much benefit the engine derives from the vacuum in the condenser. We are also furnished with the necessary data for calcu- lating the average pressure of the piston during the stroke, and from this determine how much work it is doing, and as the dis- tribution of this pressure is apparent w r e are able to calculate its rotative effect upon the crank-pin at any point in the stroke in con- nection w r ith the momentum and inertia of the reciprocating parts. In fact a properly taken diagram with all data concerned is full of interest and instruc- tion, and its study can be carried to great refinement. The most simple rule for figur- ing the diagram is to set down the length of the spaces formed by the vertical lines from the base in measurements of a scale accom- panying the indicator, and on which a tenth of an inch usually represents a pound press- ure; add up the total length of all the spaces, which w r ill give the main length, or the main pressure upon the piston in pounds per square inch. Example, lay the indicator 88 card off in ten parts, and knowing the scale to be sixty, and the ordinates (or parts) ten, and the sum of their length, six inches=6- 10 .6X60=36.0 36 pounds pressure against piston. Q. How do we understand the horse power of an engine. A. The horse power of an engine is equal to lifting 33,000 pounds one foot high in one minute. Q. How is the horse power calculated? Give various simple rules. A. Rule one, multiply the area of piston head face in square inches by the steam pressure in pounds, and the answer by the travel of piston in feet per minute, and divide by 33,000. This will give the nominal horse power. For actual horse power deduct }i in automatic and y 2 in slide valve engines. Ex- ample: engine 12X24, speed 100 "revolu- tions per minute, boiler pressure, 80 pounds piston area, 113 square inchesX8o=9,o4oX 400, feet traveled=3,6i6,ooo ■*■ 33,000=109 nominal horse power, or 73 actual horse power, in automatic cut off engines, or 54^ horse power in slide valve engines. This reduction is made for friction, average pres- 8 9 sure, condensation, etc., and is found to be quite correct in practice. To find horse power to elevate water a given height. Total weight of water in pounds multiplied by height in feet, divided by 33,000, equals horse power. LOCOMOTIVE BREAK DOWNS. Q. How and when do you block the crosshead when disconnecting? A. Ports should be covered first, before blocking crosshead. With some of the mogul engines the crosshead should be blocked in front end of guides on account of piston rod key being so long and catching the pin on forward driver. Some of the mogul engines, with all side rods down, key in crosshead will strike pin on front wheel. Q. How do you keep the packing rings out of the counter bore? A. When disconnecting, I would put a small piece of wood between end of cross- head and end of guides. Q. Would you take out the cylinder cock at the end piston is in? A. Not necessarily, if the crosshead is well blocked. 9° Q. What would you do if main rod strap or crosshead should break? A. With a broken main rod strap, I would place valve over steam ports and clamp valve stem, disconnect valve rod, take down main rod and broken strap, and block crosshead. If crosshead broke and did not come off piston rod, would block it in back end of guides. If piston broke off cross- head, would push crosshead and piston to forward end of guides and block it there, if it did not knock out cylinder head. Q. What is done if side rod or back pin breaks? A. If side rod or back pin breaks, take down both side rods. Q. Can all four-wheeled switch engines be run with the side rods down? A. No; on some switch engines the eccentric is on the forward shaft, and the main rod connected to the back wheels. On some of them, with both side rods down, a crosshead key would strike the pin on the front w T heel and would have to be cut off or else driven out, and a liner put in along- side of the key, so as not to allow it to go through too far. 91 Q. Why do you take rods down on the opposite side to that broken? A. Because if left up, and the engine should slip, the back wheels while on the center are liable to slip out of tram and break the rod or pin. O. What is the effect of sanding the rail while engine is slipping, without first shutting off steam. A. It is liable to break a crank pin or rod. Q. Is it good policy to allow sand to run from one pipe only? A. No; it is liable to twist the driving axle or break a pin. The adhesion of the engine to the rails is nearly all on one side, and has a tendency to twist. Q. How do you block up an engine with a broken driving spring or hanger? A. If main spring was broken, or hanger, run back wheels up on wedge, and block between main box and frame, then move back wheel off wedge and run main wheel upon wedge and block end of equalizer up level, and take out broken parts of spring and hanger. Q. With broken equalizer? A. Would take out broken equalizer and 92 springs, and block up the same as with broken driving spring. Q. With broken engine truck, spring, or hanger? A. Would raise front end of engine up, and block up on top of truck equalizers. Q. With broken intermediate equalizer on mogul? A. Would run main drivers up on wedges, then block between top of forward driving boxes and frame, then take out broken parts of equalizer. Q. With broken engine truck center pin on mogul, what is to be done? A. Would block up, the same as with intermediate equalizer, but, in addition to this, would have to block up forward end of intermediate equalizer to keep it off truck axle. Q. What do you do when a tire breaks and comes off the wheel on a standard en- gine? A. If tire broke and came off main wheel and did not injure the rods, would leave rods up and take out oil-cellar, take down ped- estal brace and put block of wood up under shaft, putting brace up again, then run main wheel up on wedge, then block up between 93 top of back box and frame and block be- tween main-spring saddle and frame, then run wheel off wedge, and you are ready to go. With back tire broken off, if the engine had to be backed up any distance on crooked track, would take both side rods off and carry both back wheels off the rail by run- ning them up on two wedges and block up on top of both main boxes under frame, and block under both back-spring saddles and put a block on top of bar between engine and tender and under chaffing iron on en- gine, and carry part of the weight of engine on tank, and would block under both oil- cellars. Q. With front tire on mogul or ten- wheel engine? A. If broke front tire of mogul, and it was not safe to run, and could not get tire off, would take down all side rods then run front wheels up on wooden wedges and block up on top of both main boxes under the frame and under both spring saddles on top of frame and block under male casting of engine truck and on top of female cast- ing; some large nuts would be the best to use to block up between these castings; take a piece of telegraph wire and run through 94 holes in the nuts and fasten them solid around the male casting, and drive block under each oil-cellar of the wheels which are carried off the rail and move engine off the wedges and you are ready to go. Q. Main tire on mogul? A. If main tire on mogul broke and came off and injured side rods or main rod, would take down all side rods and place valve over steam ports, clamp valve stem, disconnect valve rod and take down main rod, and if piston rod key would strike front pin, would block crosshead in forward end of guides, would take oil-cellar out of wheel with tire off, take down pedestal brace, and put a hardwood block under shaft, then put ped- estal brace up again, run wheel up on wooden wedge and block up on top of back box under frame, and on top of front box under frame, and block between saddle and frame over wheel that is off the rail, then run engine off the wedge and you are ready to go. If tire is broken and it is not safe to run and could not be gotten off on the road, would take down all side rods; if I could run the engine on the wedges, would run both wheels up and block up on top of both back boxes under frame and on top of both 95 front boxes under frame, drive a block un- der each oil-cellar and block under both main spring saddles, then cover steam ports on both sides and clamp valve stems and disconnect valve rods, take down both main rods, and if piston rod keys will strike front pins, block the crosshead in front end of guides, or the center of guides, and you are ready to be tow r ed in. Engine will have to be moved off from wedges with another engine or pinch bar. Q. With the back tire on mogul? A. If back tire on mogul broke and came off and did not injure side rods, would take out oil-cellar and put wooden block under shaft, then run wheel up on wedge and block between top of main box and frame, then move engine off wedge and you are ready to go. Q. With both back tires on mogul? A. If tire broke and did not come off, and you could not get it off on the road and it was not safe to run, would take down both back sections of side rods and run both back wheels up on wedges, block up between both main boxes and frames, then block on top of bar between engine and tender under chaffing iron on engine, drive a block under 96 each oil-cellar and block under both back spring saddles and you are ready to go. You could not back up around curves on ac- count of both main tires being blind. If I have to back an engine up to get home, I would run her ahead to the nearest turntable or "Y M and turn around if it was not too far. If I could get to a turntable or (( Y" by backing up two or three miles, I would drop the wheel with the broken tire on the rail and cut a pole and put it between the spokes of the wheels and against the frames and skid back wheels: If I could not get a pole, I would use a chain; If both tires came off the wheels, would chain from end of frame to front beam of tender on each side and the tender would help to guide the wheels. Q. What would you do if back tire or back driver was broken off on standard engine? A. Would jack up back, take down side rods on standard engine, or back rods on mogul. Q. At what points is weight of engine carried when springs and equalizers are in good order? 97 A. The weight is carried on both equal- izing stands and center of engine truck. Q. Where is the weight carried when engine is blocked up over the forward driv- ing box? A. When blocked over the main box theu weight is the same as with the main spring in, but when the engine is in motion and the main wheel drops in a low spot in the track the weight of the main box is carried on the back spring and engine truck, and if main wheel runs up on a high spot in track, the main box would take the weight off the back spring and engine truck. The equalization of the weight between the boxes is destroyed when blocked over the boxes when the engine is in motion. Q. How is it when blocked over back driving box? A. When blocked over the back driving box, the weight is the same as with the springs in, but when the engine is running and the back wheel drops in a low spot in the track, the weight from off the back box comes on the main spring and engine truck. And if main wheel runs up on a high spot in the track the most of the weight would be on main spring alone. And if main 7 98 wheel drops in a low spot the weight would be on back box and engine truck. Q. If truck axle was bent? A. Slide the wheels by chaining same. Q. How would you know if valve yoke was broken? A. Place main pin on right side at half stroke (giving valve full movement over ports), admit a little steam into the chest and move the reverse lever forward and back, if steam shifts from forward to back cylinder cocks the right valve yoke is O. K. Then try the left side the same way. If yoke is broken, take off chest cover, center and block valve equally over both ports, discon- nect the main and valve rods, block cross- head, cover chest and proceed to nearest side track or telegraph station. Q. If throttle was detached while running • how would you act? A. If valves were balanced, would control train with reverse lever and air valve. Q. Suppose right go-ahead eccentric slipped what would you do? A. Place right side of engine on forward dead center, place reverse lever in last back notch, mark valve stem at gland, bring reverse lever to forward last notch and move 99 slipped eccentric until mark on valve stem reaches gland. Q. If right back-motion eccentric should slip? _• A. Place right side of engine on back dead center, place reverse lever in forward last notch, mark valve stem at gland, throw lever in last back notch, move eccentric until mark on valve reaches gland. Q. Suppose both forward and back eccentric on one side slipped what would you do? A. Simply place engine on forward dead center (as near as possible), set the forward motion eccentric above the shaft heavy side up, for in right angles with the crank-pin, set the back-up eccentric opposite the go-ahead; after this is done place the reverse lever in forward notch, then move the forward eccentric ahead until steam comes out of forward cylinder cock. To set back-up eccentric, place reverse lever in last back notch, move eccentric until steam comes out of forward cylinder cock, then all is O. K. Be careful when doing this, that engine wheels are blocked and throttle slightly open. Q. In case of broken back section of side 100 rods on a 6 driver engine, what would you do? A. Take off back sections, each side of engine, then pull in as much of the train as possible. Q. Suppose through some unforseen cause a cylinder head was broken what would you do? A. Disconnect the valve stem at rocker arm, tighten valve equally over ports, dis- connect mainrod and block the crosshead in guides. Q. Suppose rocker arm is broken? A. Disconnect same as for broken cylin- der head. Q. If valve stem or piston were broken? A. Do same as for broken cylinder head. Q. Suppose valve in chest were broken how would you remedy it? A. Iyift valve chest cover, cover ports with thin plank, place valve over same and block that way; if a balanced valve and nothing could be placed under valve then open front end and disconnect dry pipe from nigger head end, bolt on a blind joint made of sheet rubber and heavy board or iron plate. Q. Suppose you lost a rod key how would you proceed? 101 A. Insert a wooden key temporarily. Q. If broken valve stem outside of chest? A. Center valve and clamp with gland by drawing up more on one side. Q. What is the best material to use in blocking between driving box and frame? A. Iron plates; wood is too soft. Q. If driving box or brass breaks so it is cutting the axle, what can be done to relieve it? A. If main box brass is cutting badly, run main wheel upon a wedge, and block under saddle and on top of frame, also be- tween frame and top of back box, that will carry some of the weight. Q. Is it considered an engineer's duty to have suitable hardwood blocks on engine? A. Yes. Q. How would you block up for broken engine truck wheel or axle? A. Raise up front of engine and block between top of main boxes and frames and block on top of back truck boxes under truck frames and block across on top of both back truck boxes under main frames and carry the weight of the front wheels on the back ones and forward drivers, then chain front wheel up to front frame; then pull into 102 side tracks, best way is to send for pair of wheels and put in on road. Q. What would you do with a mogul or a pony truck when broken? A. Would run main wheels up on wedges, being careful that main rods do not strike guide yokes and frames, then chain engine truck up to main frame and all is ready. Q. For broken tender truck wheel or axle what should be done? A. Take out wheels and replace with box-car wheels, or if wheels could not be had, why take two poles and lay them length- • wise on top of the truck boxes on each side of tender and chain up the truck to the poles where the wheels come out. With some tenders, would have to put pole across top of tender and chain to pole. Q. Is it necessary to take down the main rod if the frame is broken between the cylinder and the forward driving box? A. No, not always; it all depends on how badly it is broken. Q. Would you* take down either rod if frame is broken between forward and back driving boxes? A. Not with a light engine, unless it was working badly; then I would take down both 103 side rods, because the strain would come on the pins. Q. Where is the frame fastened solid to the other parts of the engine? A. On standard engine frame is fastened to cylinder saddle, and belly-brace under boiler, and boiler braces in cab. Q. Would you disconnect the engine for a broken guide? A. Yes, if it was broken badly. Q. How do you handle an engine if throttle sticks open or dry pipe joint leaks so that steam cannot be shut off from engine? A. Reduce the pressure and handle the engine with reverse lever and brake on en- gine. Q. What will you do if throttle is discon- nected and remains shut? A. I would report and get her ready for towing in. Q. If a crank pin brass gets so hot the babbitt melts, would you cool it off with water before all the babbitt comes out? A. No, I would allow it all to escape. Q. Can you take out a tender truck brass and replace it with a new one? How? A. Yes; would take waste all out of box. take short jack and put under box and jack 104 the weight up off brass, then take out step and remove brass. If I had no short jack, would take large screw jack and place under side of tank and jack the weight off box, then take a pry and pry up the box. If I had no jacks I would put block of wood under the box and against a tie and move the engine and pull the box up on the block, and that would take the weight off brass. Q. An engine truck brass? A. Would raise up front of the engine, and take weight off truck box, then raise up truck frame and box with short jack or a pry, and replace brass. Q. When brass does not wear an even thickness at both ends, is it apt to run hot? Why? A. Yes; truck frame may be twisted, and allow the weight to bear on one end of the brass, and cause it to heat, axles sprung lightly would cause this effect, or only part of a step being on top of brass in box, or brass a little too long and one end bears on collar. Q. How often do you examine the ash- pan, grates and dampers? A. At the end of every trip. 105 Q. What are your duties after cutting off from train at the end of the trip? A. To look the engine over carefully, and any work there is to be done, report it in the book at the roundhouse for that pur- pose. Q. What are your duties in case of wreck, when your engine is off the track? A. Examine the engine over carefully, to see if anything is broken, especially around firebox, and get her ready to be put on the track as soon as I possibly could. Q. If front end is broken, but flues and steam pipes in good order, how could you make repairs on it to run in? A. Would board up front end of smoke box if there was enough left to hold the boards. THE AIR BRAKE. Q. To the best of your knowledge what do you understand by the automatic air ( brake? A. The automatic air brake is a brake applied by compressed air. Q. Why is it called automatic? A. Because its application is due to derangements, such as the bursting of a hose 106 or pipe, train broke in two, the trainmen reducing the air pressure in train pipe, or the engineer making a reduction of air with his brake valve. Q. Give an explanation of the automatic brake, its workings and essential parts? A. The essential parts of the automatic air brake is the engineer's equalizing dis- charge valve, auxiliary reservoir triple valve, small reservoir at the side of the engineer's equalizing discharge valve, the trainmen's application valve, the steam, air pump and governor, air guage, air pipe, cock, etc. Q. Of what use are the steam and air cylinders? A. They constitute the air pump, and are used for compressing air into the main reservoir. Q. Of what use is the main reservoir? A. It is used to retain and carry the air pressure pumped in with the air pump. Q. Of what use are the auxiliary drums? A. They are used to hold and furnish air for the brake cylinders when brakes are to be set. Q. Explain the triple valve and its location? A. The location of the triple valve is 107 between the brake cylinder, train pipe and auxiliary reservoir and is used to let in or out or hold the air between the auxiliary reservoir and brake cylinder. Q. For what purpose is the small reser- voir that is connected to the equalizing dis- charge valveT^ A. It is to store air pressure to force the equalizing piston down when sufficient air has been released from brake pipe, to automatically close exhaust. • Q. Where is the air first taken from when making service stops. A. From the main train pipe. Q. Where next? A. From the auxiliary reservoirs under each car, which passes through the triple valve into the brake cylinder. Q. When an engine is left standing alone and the pump running, why must the brake valve not be left on lap? A. Because the main reservoir pressure may run up to the same height as the steam in the boiler, and when the handle of engineer's valve is again placed in full release it will cause the train pipe and tender auxiliary reservoir to be charged with too high pressure, and may injure the 108 adjustment of pump governor as well as cause the tender wheels to slide on first application. Q. What position is proper? A. Running position. Q. Have brake cylinders what is called leakage grooves? A. Yes. Q- As a rule how much air is necessary to be discharged from train pipe to force the piston past the leakage grooves? A. About 5 lbs. Q. How long are the leakage grooves in the brake cylinder? A. Four inches. Q. Where are they located? A. In forward part of cylinder. Q. What are the leakage grooves pro- vided for? A. They are provided to release the brake cylinder of any air that might leak into it throngh the triple, also release the air left in brake cylinder after an application has been made. Q. Name the different positions of the equalizing discharge valve? A. There are five, namely: full release, 109 running position, on lap, service top, and emergency. Q. Why is equalizing discharge brake valve better than the old brake valve? A. Because it enables the engineer to apply the brakes more uniformly through- out the train, and with less shock, especially when quick action triple valves are used. It also prevents the brakes on forward end of train from being kicked off when engineer closes the valves after having made applica- tion. Q. Name the different kinds of engineers' brake valves, to the best of your knowledge. A. The D 8 and D 5. Q. What divides the main reservoir pres- sure from the train line pressure? A. The equalizing discharge valve. Q. On which side of the equalizing dis- charge valve is the main reservoir pressure? A. On top. Q. On which side of the rotary valve in the old-style engineer's valve is the main res- ervoir pressure? A. Below. Q. What air pressure operates the pump governor in the D. 5 and D. 8 valve. A. With D. 5 brake valve the main reser- 110 voir, and with all others the train pipe pres- sure. Q. Suppose [the governor does not regu- late the train line pressure, how would you adjust it with the D. 8 valve, also the D. 5 ? A. With D. 8 valve the train line pres- sure is regulated by the pump governor, the spring in governor should be set so 70 pounds of air pressure will raise the dia- phragm and air valve, so air will go down on governor piston and force the steam valve shut. With the D. 5 valve the train line pressure is regulated by the feed valve or train line governor on the side of brake valve. Set spring in feed valve so it will let the train line pressure move feed valve pis- ton down with 70 pounds pressure, this will let feed valve close so no more air can pass from^main reservoir through running posi- tion port to train line, and pump governor should set at enough higher pressure to carry the desired excess pressure. Q. Why is governor regulated to only allow 70 lbs. of air pressure in train pipe ? A. Because 70 lbs. train pipe pressure produces the strongest, safe to use and pre- vents sliding of wheels. Ill Q. Explain the difference between the plain and quick action triple valves ? A. The plain triple valve has the cut-out cock in the body of the valve; the quick- action has it in the cross- over pipe between the train pipe_and triple. The plain triple does not have the additional parts to work the emergency action of the triple, conse- quently the brake is not liable to leak either on or off through the emergency valves or checks. The plain triple used on engine tender and coach equipment is so arranged that the piston works upright, and when the train is running the jar may work it down, and cover feed port so a very light reduction will set it; the piston in quick action triple moves horizontally, so its weight does not influence the action of the triple when running. Q. What might prevent governor from shutting off the steam and stopping pump when maximum pressure is obtained ? A. The engineers brake valve being on lap. Q. If the piston in equalizing discharge brake valve becomes corroded and gummed what will be the result ? A. It would be necessary to make a large 112 reduction through the preliminary exhaust port before the brakes will apply at all and then the brakes will go on too hard and will have to be released by hand. Q. At what travel should a driver brake piston be adjusted? A. Not less than y$ or more than 2 /i its full stroke. Q. How is the brake-shoe slack of the cam driver brake taken up and what pre- cautions are necessary ? A. By means of the cam screws, and it is necessary to lengthen both alike, so when brake is applied the point of contact of cams will be in straight line with piston rod. Q. How is the brake-shoe slack of a six- wheel connected driver brake taken up ? A. By means of a turn buckle or screw in the connecting rods. Q. How would you take up slack of ten- der brake shoes ? A. By means of the dead truck lever. Q. Suppose they would not take it up enough; where then? A. It must be taken up in the under- neath connections and then adjusted by the dead lever. 113 Q. What distance should the brake cylin- der piston travel under tender brake ? A. Not less than 5 nor more 6 inches; adjustments must be made whenever the piston travel is found more than 7 inches. Q. How often should triple valves and cylinders of drivers and tender brakes be cleaned and oiled ? A. Every 6 months with mineral oil; oil cylinders every 3 months, and driver brake cylinders oftener if close to fire-box. Q. How often must the air brake and sig- nal apparatus on locomotives be examined ? A. After each trip. Q. What pressure of air must be carried on passenger engine and main train pipe ? A. 70 lbs. Q. On freight? A. 70 lbs. Q. What should the excess pressure be, also the signal pressure ? A. Excess pressure is 20 lbs., and signal pressure is 25 lbs. Q. Do you understand the necessity of keeping the feed valve and excess spring clean ? A. Yes, so it will maintain an excess pressure of about 20 lbs., in the main reser- voir and to insure release and recharge train quickly. Q. Why is excess pressure necessary ? A. It is to recharge auxiliary reservoirs quickly. Q. After the engine is backed up to train what should be done ? A. The air cock should be opened and the hose blown out, then connect to train hose, after that the engineer's brake valve should be placed in the release position, so train pipe, auxiliary reservoir and main reser- voir come in connection and equalize with air. Q. What is next to be done ? A. Test the air and brakes to see that all parts are in order before starting out on a run. Q. Suppose the pipe between brake cyl- inder and auxiliary reservoir was split or broken off, and prevented the operation of the triple valve, what should be done ? A. Move triple valve midway and open bleed cock under auxiliary reservoir. Q. Will that interfere with the rest of the train ? A. No. Q. About how much loss of air out of 115 train pipe is considered to firmly set all brakes ? A. Generally about 1 8 or 20 pounds. Q. Suppose after having recharged the train pipe from main reservoir and released all the brakes but the one under tank, where would you lookTfor trouble ? A. Examine triple valve and see if it is up, if not, then move up and equalize air. Q. Give the different forces with differ- ent cylinder diameters and the brake piston traveling at eight inches in all ? M 03 u pq . "is a °o 2*d So c3"S £wph £1h Total Force From Piston, in Pounds. a P-CJ 3.S O Pi O u 70 63 7 4 600 300 200 100 61 9 19 1900 1500 950 500 59 11 26 4000 2050 1300 700 57 13 40 6150 3150 2000 1100 55 15 46 7100 3600 2300 1500 53 17 50 7700 4000 2500 1400 51 19 21 23 50 50 50 49 47 Q. Is there a limit to the braking power of the automatic brake ? A. Yes. 116 Q. What governs it ? A. The triple valves, graduating valve. Q. Can you tell by the gauge when this limit is reached ? A. Yes. Q. What pressure is in cylinder when 70 lbs. pressure is in auxiliaries ? A. 50 lbs. Q. What are the functions of the triple valve? A. It is to automatically open and close the auxiliary reservoir valve when pressure is increased and decreased in main brake pipe. Q. Why is it called a triple valve ? A. Because it connects and operates three points, namely: main train pipe, auxiliary reservoir and brake cylinder. Q. Where is the compressed air kept ready for use ? A. In the main reservoir about engine. Q. Where does the compressed air come from that enters the brake cylinder when the automatic brakes are applied ? A. It comes from the auxiliary reservoir. Q. How does it get into the auxiliary reservoir ? 117 A. From the main train pipe through the triple valve. Q. About how many seconds does it take for the auxiliaries to recharge with air ? A. About two seconds. Q. When two or more engines are coupled together, which one should do the braking ? A. The head engine. Q. How would you proceed to give the forward engineer complete control of the train ? A. Engineer on second engine must close stop cock under his brake valve leading to train pipe, place brake valve in ' "running" position so as to give leading engineer full control of the train. Second engineer must keep maximum pressure up in main reser- voir to use in case head engine gives out. Q. What should the leading engineer do ? A. Make a terminal test of train, etc. Q. What is the pressure retaining valve, and what is its use ? A. The pressure retaining valve is at the exhaust of triple valve. It is used to pre- vent the brake release on heavy grades and hold the brakes partially applied so as to allow more time to recharge the auxiliary reservoirs. 118 Q. How much pressure does the pressure retaining valve keep in brake cylinder ? A. It retains 15 lbs. pressure in brake cylinder when triple valve is in release. Q. In descending a grade how can you best keep a train under control ? A. Apply brakes and reduce speed before too much speed is attained; keep a reduction of 8 pounds of air on train pipe, then re- charge the auxiliary reservoir so to have air when needed. Q. Suppose the air pump should happen to play out descending a long steep grade, with from 30 to 50 cars of air, how could you keep up the pressure in main reservoir, and the air pump stopped entirely ? A. By what is known as Sweeney's emergency brake. Q. Explain what is meant by Sweeney's emergency brake ? A. On the steam chest of cylinders is a small valve with a rod running from its handle back under the running board to cab. This merely connects the steam chest, by means of a pipe, to the main air drum; in descending a hill and no steam being used, simply open the valves to the Sweeney auxiliary pipe and reverse the engine both 119 pistons of the engine pumps air into the main reservoir and very fast. In this way an engineer can keep his full drum pressure up easily by letting the cylinders help him out occasionally. Q. Would you reverse an engine with driver brakes set ? A. No. Q. Why not ? A. Because it would block the drivers and cause flat wheels. Q. Why are three lines of hose coupled between the engine and tender on some of our engines ? A. One for main train pipe, one for air signal and the third for steam to heat train, etc. Q. Why only two on some engines ? A. One for main train pipe and one for air signal. Q. Why only one on some engines that have both driver and tender brake ? A. The one hose covers all on main train air pipe. Q. In case the lines of hose are coupled up wrong between engine and tender, can the brakes be worked ? A, No. 120 Q. How will you detect the ones that are coupled up wrong ? A.* First, try to release the brakes; if they will not release they are wrong ; couple properly, then test air signal; the last is bound to be O. K. Q. What must be done with the hose coupling back of last car and at pilot ? A. They should be hung in the dummy coupling. Q. State the importance of this. A. It is done to keep out dirt, also to prevent the hose from being torn or pulled off, etc. Q. When engineer's brake valve is on lap position and the main reservoir or train line pressure increases, where would you locate the trouble ? A. Locate the trouble at the rotary valve, being cut or leaky. Q. How often should the engineer's brake valve be cleaned, oiled and looked after? A. About every 60 days. Q, If there was a continuous leak from exhaust of triple valve, what would be the trouble ? A. Dust or dirt getting in on the road. Q. Could you remedy it on the road ? 121 A. Most generally, by suddenly opening and closing triple valve the air will clean it. Q. When does the triple valve move ? A. When the engineer moves the engin- eer's valve to the full left the train pipe is put in connection with the main reservoir valve and lets the air from the main reservoir into the brake pipe, the triple valve moves up, equalizes the pressure between the aux- iliary reservoir brake pipe and main reser- voir ; this opens the brake cylinder valve and releases the brake. Q. What would happen if the engineer moved the engineer's valve handle between the two laps, closing the main reservoir valve and letting the air out of the brake pipe? A. The triple valve would move down and connect the auxiliary reservoir to the brake cylinder and apply the brakes. Q. State the object of having two needles on air gauge, also the two colors, red and black ? A. The red needle is to show the main reservoir pressure and excess of 20 lbs. = 90 lbs., the black one is to show the mount of air in train pipe, 20 lbs. 122 Q. What do you consider an ideal man- ner of breaking ? A. Move engineer's brake handle to service stop position until the train pipe needle shows a loss of about 8 lbs.; then move handle in lap, and gradually bring the reduction down to 20 lbs. and hold there until about to stop, then release just before stopping; on a heavy grade keep brakes on. Q. In making service stop, why release the brakes before coming to full stop ? A. To prevent sudden shock to passen- gers and train. Q. Is it dangerous to apply and release brakes more than once in making stops ? A. Yes. Because every time brakes are released the air in brake cylinders is wasted, and if necessary to suddenly apply again for some unforseen cause, before sufficient time has elapsed to re-charge auxiliaries, the application will be w T eak. Q. In making a service or regular stop why must the brake valve handle not be moved past the position for service appli- cation ? A. Because in doing so the air would all be lost. 123 Q. Why is it dangerous to apply and release the brake repeatedly in making a service stop? A. Because in so doing the air would be lost. Q. In releasing brake how long should the handle be left in the same position ? A. Until theT train pipe needle shows the same pressure as main reservoir, then move handle in running position against stop. Q. What is meant by a terminal test ? A. It means to try the air and see that all is O. K. before going on a run. Q. Why is it absolutely necessary ? A. Because all the auxiliary reservoirs must be equalized in pressure with main reservoir, that all couplings are correct, and that the brakes work satisfactorily. Q. At what other times should tests of the same nature be made ? A. When a car is picked up on the road or one in the middle of the train is thrown out, or any switching, etc., is done. Q. In picking up uncharged cars what should be done ? A. After coupling to car move the handle of brake valve in release, so to fill auxiliary 124 reservoir when cocks are opened between the cars. Q. Why are brakes released before un- coupling cars ? Q. If train was broken in two, how would you proceed to get under way again after coupling up, and what w 7 ould you do ? A. Place brake handle on lap and leave it there until train has stopped and the brake apparatus has been examined and a release signal is given, after coupling up again await signal to test brakes after having charged aux reservoirs. Q. How would you get the train ready ? A. Place handle of brake valve in full release, then in running position, then await test signal, then test brakes, etc. Q. Would it be necessary in this case to make what is called a terminal test? A. Yes. Q. Why? . A. To be sure everything about the braking power is O. K. Q. Suppose trainmen cut out a car, what should be done ? A. The handle of engineer's brake valve should be moved into full release to equalize the auxiliaries and train pipe. 125 SPEEDING AND SIGNALS. Q- Give as near as practicable the dis- tances of telegraph poles, also how many to the mile. A. The telegraph poles are supposed to be K 55 feet apart, and 32 poles to the mile. Q. Suppose you were running 45 miles per hour how many minutes and seconds would you allow to each mile ? A. One minute and 21 seconds. Q. To 25 miles? A. Two minutes and 24 seconds Q. To 10 miles? A. Six minutes. Q. To 58 miles ? A. One minute and 2 seconds. Q. To 30 miles ? A. Two minutes. Q* To 35 miles ? A. One minute and 42 seconds. Q. To 15 miles? A. Four minutes. Q. To 55 miles? A. One minute and 6 seconds. Q- To 40 miles ? A. One minute and 30 seconds. Q- To 20 miles ? A. Three minutes. 126 Q. To 50 miles ? A. One minute and 12 seconds. Q. To 60 miles ? A. One minute. Q. How would you find the time it would take to travel a certain distance, making a certain speed per hour ? A. Multiphy the distance by 60 and di- vide by rate of speed. Q. Give an example: A train running from station to station, say distance is S}4 miles, and the rate of speed is 28 miles per hour, how long will it take to make the %% miles ? A. 8J^ miles x 60 = 510 h- 28 miles =18^3 minutes. Q. Can you give the distance and the time to find the rate of speed ? A. Yes. Multiply the distance by 60 and divide by the time ? Q. If it takes a train 18^3 minutes to run S}4 miles at what rate of speed does the train run ? A. S}4 miles x 60 minutes = 510 h- 18^3 == 28 miles per hour. Can you give the time and the rate of speed to find the distance ? 127 A. Yes. Multiply the time by the rate of speed and divide by 60. Q. If the train is running at the rate of 28 miles per hour of 18^3 minutes what is the distance passed over ? A. iS}i x 28 = 510 -- 60 = 8^ miles, the number of miles passed over in 18^3 minutes at a speed of 28 miles per hour. To those who prefer to use formula, I give the following: Let T=Time in minutes. R=Rate of speed, in miles, per hour. D=Distance in miles. 6o=Constant. I. Given, R and D, to find T. Solution: f X D = T. II. Given, D and T, to find R. Solution: 60 - -£- = R. III. Given, T and R, to find D. Solution: T--^-=D. Q. How do you understand the SIGNALS IN GENERAL. BEU/-CORD OR ENGINEER'S AIR WHISTLE. One tap when standing still — Go ahead. Two taps when running — Stop. Two taps when standing — Call flagman. 128 Three taps when standing — Back up. Three taps when running — Stop next sta- tion. Four taps when running — Reduce speed. ENGINE WHISTLES. One long whistle, stations, draw bridges, junctions and R. R. crossings. One short whistle — Stop, on brakes. Two medium whistles— Start, off brakes. Two short whistles — Answer to all signals except when broke in two. Three long whistles — Train parted. Three short whistles when standing — Back up. Three short w r histles when running — Call attention to signals carried. Four long whistles — Calls in flagman. Four short whistles — Switch or signals. Two long and two short wrhistles — Wagon- road crossing. Five short whistles — Send out flagman. Continuation of short whistles — Stock on track. LAMP AND HAND SIGNALS. Raise hand or lamp up and down — Go ahead. Swing hand or lamp across track — Stop. 129 Swing hand or lamp in circle to left — Back up. Swing hand or lamp at full arm's length until engineer answers by three long whistles, Broke in two. SIGNALS CARRIED BY TRAINS. Two green flags or lamps in front of engine — Another section following with same rights. Two white flags or lights in front of engine — Special or wild train. The lights on freight caboose are one cupola light, green front and red back, two lamps, one each side of car, each having front and sides green and back red. Day signals are green flags. The lights for passenger trains are the same except in place of a cupola light a large red bull's-eye sits on rear platform of last car. STATION OR FIXED SIGNALS. Red flag or light — Danger, stop. Green flag or light — Caution, slow. White flag or light — Safe, clear track. White flag or light at station — Stop for passengers. 9 130 Red flag or light at station — Stop for train orders. TORPEDO SIGNALS. One torpedo — Stop. Two torpedoes— Slow speed, careful, look out for signals. Place one torpedo about ten telegraph poles from train or 1,600 feet, then go still further 1,600 feet and place two about 20 feet apart, leave the two torpedoes and go> back to the single one, stay in that neigh- borhood until engineer blows four long; whistles, then remove torpedo and run toward train; if passenger train is due wait, signal and ride in. Never place torpedoes near depot or wagon-road crossing. Q. Name the different makes of switches. A. The point or split switch, double split and old stub switches. Q. What is a Y track and its use? A. AY track is two tracks from two dif- ferent directions off main track, running to- gether, forming a Y. It is used to turn engines, trains, etc. Q. Explain the Block system. A. It is a system of working railway traffic, according to which the line is divided . 131 into sections of a mile or more, with a signal and telegraphic connection at end of each section. The principle of system being that no train is allowed to leave any one section until the next succeeding section is entirely clear, so that between two successive trains there is preserved definite intervals of time and space. Q. What is meant by a semaphore? A. A semaphore is a post th^ 4- bears tar- get signals. Q. Explain semaphoric. A. Semaphoric means targets operated by electricity. Q. What is a railroad gauntlet? A. A railroad gauntlet is the running to- gether of parallel tracks of a double road passing in the space of one, going through a single tunnel or bridge without breaking the continuity of either rail. Q. Suppose the target stood out at right angles with post and not in your favor, what would prevent you from going right along? A. If by accident such a thing would happen, the engine would run off the end of rails, and that would qualify me for about 30 days' uncalled for vacation. MIXED QUESTIONS AND ANSWERS. Q. What does a ton of soft coal contain? A. It contains 2,000 cubic feet of gas, 1,500 pounds of coke, 20 gallons of am- monia water and 14 pounds coal tar. Q. How would you find the area of any cylinder? A. Multiply the diameter by diameter and answer by .7854. Q. How many area square inches has a cylinder 16-inch diameter? A. It has 201.06 square inches. Q. State the different standard decimals used daily, namely, to find the circumference of any diameter's circle; also to find the cubic inch contents of a ball? A. Standard number for circumference is 3.1416, and the standard number for cubic inches in a sphere use .5236. Q. How do you understand a cubic? Explain by example, say a ball is 3% inches diameter. A. A ball 3^ inches diameter reads 375 X 3.75=14.0625 x 375 = 52.734375 X-5236 =27.61 17187500=27^0 cubic inches in ball 3^-inch diameter. Q, Does it take more air to burn coke than coal? 133 A. Yes, it takes one-tnird more air for coke than coal. Q. How many cubic feet of air does it take to consume one pound of coke? A. It takes 330^3. Example: 248 for coal; Ys of 248= 82^, added to 248= 330^. Q. How are fractional parts of whole numbers made to read as whole numbers? A. The fractional part of a whole num- ber is made to read as a whole number by dividing the fractional part into 100 until nothing remains; answer will be fractional part in decimals, Example: % of 100, 4^-ioo=.25X3=75- Q. How are they found, take T \ of $1, for instance? A. One=$i.00. Divide 16 into 100 until nothing remains. 16^ 100=6.25 X 3=18.75, or i8^c= T 3 e of $1.00. Q. How do you understand the horse power of a boiler? A. The evaporation of 1 cubic foot of water per hour. Q. How do you understand the horse power of a steam engine? A. 33,000 lbs. raised 1 foot high in I minute. Q. Give an explanation of a horse power? 134 A. First compare the rule with the actual power of a horse, and then apply it to the steam engine. The usual traveling gate of a horse, hitched to a light sulky is about 5 miles an hour, or 440 feet per minute. If a spring scale be attached to the singletree we may note the amount of power the horse is exerting. Assuming this to be 75 lbs. and the product of the speed per minute 440, multiply speed by lbs. or power exerted and the answer is 33,000 foot lbs., and rep- resents a horse power. Q. How is this applied to an engine? A. In applying this to an engine, we first find the area of the cylinder, mutiply area by boiler pressure, and that answer by pis- ton speed in feet per minute, and divide by 33,000. Answer will be nominal H. P. Q. What deduction for cut off? A. Deduct }i. Q. How much for short cut-off? A. Deduct j£. Q. Why is this reduction made? A. It is made for variation of pressures- friction, condensation, etc. Q. Are you acquainted with any short rule by which a cylinder H. P. can be rated? A. For small cylinders, from 2 to 12 inch 135 bore ; multiply diameter by itself and divide by 3. Answer is H. P. For larger cylinders from 16 to 20 ; divide by 4. Answer is H. P. Q. Explain why engines with large cylin- ders as a rule have 3, 4 and 5 drivers on one side, also all of them connected? A. The more drivers the more traction on the rail and the more load can be started. The reason for connecting all is more trac- tion, and the heavy strain on the main pin divided up between other pins through the parallel rods. Q. Is the piston-head in the middle of the cylinder's length when the crank pin is at either half stroke? A. No. Q. What is the cause of this? A. It is caused by the main rod's length. Q. Which travels the greater distance in one revolution, the cross head or the crank pin? A. The crank pin, Q. How much further does the crank pin travel than the crosshead in one-half revo- lution, also in one revolution? A. The crank pin travels one-sixth fur ther in a half revolution and one-third in one revolution. Q. Does the crosshead stop in the guides at each dead point? A. Yes. Q. What is the crank pin doing while the crosshead is at dead point? A. It is traveling one-sixth of the circum- ference. Q. How many sixths are there in the travel of the crank pin? A. There are six, one at each dead center divided into twelfths, and two for each full stroke of crosshead=six. Q. What is the object in beveling engine and car wheels? A. They are beveled to make up the dif- ference as much as possible between the short and long rail in turning a curve, also to keep the train central between the rails. Q. How does one know where to look for tensile strength, and what is tensile strength? A. Generally the sheets are stamped, giving the exact T. S., and the meaning of the term is the amount of the hydraulic strain the sheet will test to per square inch in pulling asunder. Q. Is it rulable to use full T. S. in work- ing a boiler? A. No; about one-sixth of it. 137 RULES AND RECIPES. To compute the speed of shafts, size of pul- leys, etc. Example : To find the size of a driven pulley to give a shaft 160 revolutions driven by a 32-inch driver running 96 revolu- tions; simply multiply the driver, 32, by the speed it runs and divide by speed wanted. 96x32 = 3072 -f- 160 = 19-inch pulley. * TO TEST QUALITY OF IRON. A soft, tough iron is known by fracture giv- ing long silky fibres of a grayish hue, and the fibres covering and twisting together before breaking. Badly refined iron is known by its short blackish fibre. Brittle iron is indicated by coarse grain with brilliant crystalized break. This iron works easy, and welds easily when heated. TO TEST STEEL. Good tool steel will fall to pieces at a white heat; at a bright red it will crumble under the hammer; at middle heat it may be drawn to a needle point. To test hardening qualities : Draw under a low heat to a gradually tapered square point and plunge into cold water; if broken point will scratch glass the quality is good. 138 Recipe to Polish Boiler-Heads, Fire- Boxes, Smoke-Arches, Stacks, Etc. — Take an old sponge and common soap and make a suds; pour on some boiled oil and rub over boiler-heads, etc. This will leave a satin gloss polish instantly; do while warm. Receipt to Cool Hot Pins, Journals, Etc. — Use small quantity of ammonia; work it through the oil cup; it will surprise you. Pulverized sulphur and plumbago mixed with machine oil is very good. Calendar Calculations. — Rule to find on which day of the week any date will fall, in the future or past. Example: Set down the last two figures of the year, say 95. The y± of 95=23 (dropping the fractions), then add the date desired, say Feb. 3; then add the standard number following the month of February, which is 6; add all together and divide by 7, which are the seven days of the week; the answer remaining is 1; there- fore Feb. 3, 1895, falls on the 1st day, Sunday. 95 year. 23 X year. 3 days. 6 Month No. 7)127(18 126 1 Sunday. Months with standard numbers: Jan. 3, Feb. 6, March 6, April 2, May 4, June o, July 2, Aug. 5, Sept. 1, Oct. 3, Nov. 6, Dec. 1. 1 remaining represents Sunday. 2 " Monday. 3 " Tuesday. 4 u Wedn'day. 5 ' Thursday. 6 1 Friday. 7 or " 1 Saturday. 139 To test tenacity : Take a hardened piece and drive it into cast iron with hardened ham- mer; if poor it will crumble. Soft steel of good quality gives a curved line break and gray texture. Tool steel should be a dull silver color, equal and entirely free from sparkling qualities. Aquafortis, applied to the surface of steel, produces a black spot; and on iron the surface remains clean. The slightest vein of iron or steel can be detected by this method. To remove dust from steel, brush the rusted steel with a paste composed of y 2 oz. cyanide of potassium, y 2 oz. castile soap, one oz. whiting and enough water to make a paste; then wash the steel in a solution of y 2 oz. cyudide of potassium in two ozs. of water. TO CLEAN BRASS. Take and mix one part common nitric acid, y 2 part sulphuric acid, in a stove, having also a pail of fresh water and a box of sawdust. Dip articles into acid, and then soak in water, and finally rub them in sawdust, and the brass will be bright. If the brass is greasy, first dip into a strong solution of potash and soda in water; then rinse, so the grease may be removed, leaving the acid free to act upon the brass. 140 To keep machinery from rusting : Take one oz. of camphor and dissolve it in one pound of melted lard; take off the scum, and mix in as much fine black as will give it iron color. Clean the machinery and smear it with the mixture. After 24 hours, rub clean with a soft linen cloth. It will keep clean for months under ordinary circumstances. BOILER COVERING. Take 16 pounds of rye flour, 32 pounds flax seed meal and 15 gallons of water, boil for one hour; then add three pails of dry clay, three pails of sifted ashes and seven pounds of hair. The above proportions will make about one barrel. For outside finishing, use half the amount of hair. CEMENT. Cement to fasten iron to stone; when made, use at once. Take ten parts of fine iron filings; thirty parts of plaster of paris and j£ part of salammoniac, mix with weak vinegar to a fluid paste, and apply at once as it sets very quickly. To avoid tearing manhole gaskets, put a little white lead on the surface of the gasket, which rests on the manhole plate, and chalk the outer surface of the gasket heavily, as 141 also the part of the manhole frame with which it comes in contact. STEAM HEATING. Allow one square foot of heating surface in a boiler for every 200 feet of space in a church] in a dwelling allow one square foot to every 50 cubic feet. The radiators should have one square foot of superficial area to every six square feet of glass in windows, and one square foot for every 80 feet to be heated. One horse power in a boiler is generally sufficient for 40,000 cubic feet of space for a temperature of 70 degrees Fahr. CAPACITY OF TANKS. To ascertain the capacity of a tank, multiply the square of the diameter by 5.873 and the re- sult will give gallons for one foot in depth. Example : Tank 10 feet in diameter 10x10 = 100x5. 873 = 587 gallons. To find ca- pacity of square tank in gallons multiply length by breadth, then by height in inches^ cubic contents and divide by 231 (number of cubic inches in a standard gallon). Safe working pressure of a boiler : Multiply ttvice the thickness of the shell by the tensile strength (found stamped on boiler sheet) and divide by the diameter of the shell in inches. 142 Rule to determine weight on safety valve lever : Multiply area of valve by pressure of steam per square inch wanted to blow off at ; from this answer subtract the weight of lever, valve, stem and pin; then multiply the remain- der by the distance from the valve to the ful- crum; divide by the distance from fulcrum to where weight is to be placed; the answer will be the required weight TO CUT A GLASS GAUGE TUBE. If tube is too long, take a three-cornered file and wet it; hold the tube in one hand with the thumb and fore-finger at the place where you wish to *cut it; saw it quickly and lightly two or three times with the edge of the file. Now take the tube in both hands, both thumbs being at the opposite side to the mark and about one inch apart, then try to bend the glass, using your thumb as fulcrum. It will break at the mark every time. LIME WATER. To make a lime water for scalds and burns : Slack a small piece of lime; as soon as the water is clear, mix it with linseed oil, enough to make a cream-like substance. This will ex- clude the air from the burnt parts and allay in- flammation almost instantly. 143 CALCULATING INTEREST, SHORT RULES. If at six per cent, multiply the dollars by the number of days and divide by six, and cut off one figure on the right. Example : what is the interest on $73.25 from April 12th to July 15th, which is 94 days? 73:25 X 94=6885-^-6=$1.15. If at seven per cent, after following above rule, add 1-6 thus, 1.15 + 19 = 11.34. If at five per cent, after following the rule, deduct 1-6 thus, 1.15-1-9 = 96 cents. BRICK WORK FOR BOILERS AND ENGINE BEDS. The size of a common brick is 2.66 X 3.85 X 7.70 ; the size of a fire brick is 2.66 X 4| X 8$. Weight of brick work is ll2 pounds per cubic foot ; weight of stone work is from 116 to 144 pounds per cubic foot, 21 bricks equal one cubic foot, 4J bricks laid flat equal one superfi- cial foot. In setting boilers use only the best hard brick for walls, and the best fire brick for lining furnace surfaces. If the boiler has side lugs to bear its weight, the forward lugs should rest directly on lug plates placed on the walls, and the rear lugs on expansion rollers placed crosswise on the wall plates under the centre of iugs. Keep the brick work away from the lug3 over expansion rollers, you will not be bothered with cracked walls. The bridge walls should be faced and capped yylih fire brick, and built up within six inches of the shell, sloped toward the back, circular with the boiler. The flue at back of boiler should be formed by an arch spring from side- walls, or by wrought iron plates covered with two thicknesses of brick, these plates to be sup- ported by T iron cross-beams set flush on under side and below the manhole of boiler or below the water line. To know the number of bric&s it will take to set a boiler in 12 inch walls: multiply length of wall by height in feet, and multiply by 21 (the number of bricks in a cubic foot.) Example: wall 15 feet long, 8 feet high, opposite wall the same, rear wall 5X8, bridge wall 5 feet long, 2 feet wide, average 3 feet high; 15 X 8 = 120 two walls = 240 5X8=40 5X2 = 10X3 = 30 240 + 40+ 30=310 cubic feet; which multiplied by 21 = 6510 bricks. This will take 6 J barrels of lime and 6J barrels of sand as mortar. Allow- ance is to be made for the covering of top of boiler paving ashpit and for fire brick in build- ing front connection, Use only fire clay in fur- nace. Lime mortar mixed with very little ce- ment is good for pits. Lime mortar stands heat better than cement. ■ 145 ENGINE FOUNDATION. The foundation of an engine should be built one foot lower than the fly wheel and one width of a brick wider all around the bed plate of en- gine and 14 inches wider^t the base all around. Out bearing pillow block should be built the same in proportion and run> a stay or brace from engine bed to pillow block brick work. To ascertain the number of bricks required, find the average width and length, then multi- ply length by width by full height, and then by 21, which gives number of bricks. Use hard burnt brick or bats for filling, or fill with rubble or concrete made of three barrels of stone rub- bish, two barrels of sand, and one barrel of ce- ment, mix and wet down The foundation should be laid in cement and sand mixed, one part sand and two parts cement. To every 1000 bricks use two barrels cement and one barrel of sand. To ascertain the expansion of wrought iron pipes. Multiply the length of pipe in inches by the number of degrees to which it is heated, and divide by Ij-^q, which gives the expansion in inches. Cast iron pipe expands li^ 2 ^- of its length for each degree Fahr. it is subjected to under ordinary circumstances. Wrought iron P*P e Ip^* A. two incb pipe when heated to 10 146 338 degrees Fahr. or 100 pounds pressure, exerts an expansion force of twenty -five tons, The melting, boiling, and freezing points of various substances, and metals in alphabetic form. MELTING. Antimony melts at 951 D eg. Bismuth melts at 476 Brass melts at. 1900 Cast Iron melts at 3479 Copper melts at.....,, 2548 Glass melts at 2377 Gold melts at 2590 Ice melts at 32 Lead melts at . 594 Platinum melts at 3080 Silver melts at 1250 Steel melts at 2500 Tin melts at 421 Zinc melts at 740 BOILING. Ether boils at 100. Beg. Fresh water boils at 212. Linseed Oil boils at 340. Mercury boils at 662. Naptha boils at 186. Oil of turpentine boils at 304. Sea water boils at 213. | Sweet Oil boils at ., 412. FEEEZING. Ether freezes at 47. Belew Zero. Mercury freezes at 40. " " Sea Water freezes at 28. •< " Sweet Water freezes at 32. Above " Wine freezes at 20. " u Alcohol has no record of ever having been frozen. The claim is that alcohol has been exposed to one hundred and twenty degrees below zero without freezing. 147 HOW SOUND TRAVELS. In dry air at 82 degrees 1141 feet per second, cr about 775 miles per hour ; in water, 4,900 feet per second ; in iron, 17,500 feet; in copper, 10,378 feet; and in wood from 12,000 to 16,000 feet per second. In water a bell heard at 45,- 000 feet could be heard in the air out of the water but 656 feet. In a balloon the barking of a dog on the earth can be heard at an elevation of 22,000 feet or four miles. Divers on the wreck of the Huzzar frigate, one hundred feet under water at Hell gate, near New York, heard the paddle wheels of distant steamers hours before they^hove in sight. The report of a rifle on a still day may be heard at 5,300 yards ; a military band at 5,20ft yards. The fire of the English on landing in Egypt was distinctly heard 130 miles. Dr. Jamieson said he heard, during a calm day, every word of a sermon at a distance of two miles, The first steamboat plied the Hudson in 1807. The first saw-maker's anvil was brought to America in 1819. The first use of a locomotive in this country was in 1820. The first use of a stationary engine was in 1625. The first use of kerosene for lighting purposes was in 1826. 148 The first horse railroad was built in 1826 and '27. The first lucifer match was made in 1829. The first iron steamship was built in 1830. The first air pump was used in 1650. The first newspaper advertisment appeared in 1652. The first copper cent was coined in New Haven in 1687. How to destroy the effects of acid on clothes : dampen as soon as possible with spirits of am- monia and the effect will be destroyed immedi- ately, A good cement to stop holes in castings is eight parts of sifted cast iron turnings, two parts of powdered salammoniac and one part sulpher made into thick paste with water and mixed fresh for use is very fine. To make a fine oil for watches or fine machin- ery. Put thin strips of lead in a large mouth bottle and pour over pure olive oil, and leave it stand in the sun about three weeks, then pour off the clear oil, and you will have an oil which which will neither corrode or gum. A good varnish for boiler fronts, smoke stacks and steam pipes is good asphaltum, dissolved in oil of turpentine. Cement for joints for steam exhaust or waste pipes that will set under water : Paris white ,ground, four pounds; litharge ground, ten pounds, yellow ochre, fine, half pound; hemp, 149 one -half oz., cut short and mix all together with linseed oil to a stiff putty. TEMPERING. Tempering of fine springs, after bringing to the proper shape desired : heat slowly to a cher- ry red and plunge in black oil ; after the spring is cool hold it over the fire and burn the oil off; dip the spring in the oil three times in this man- neer and burn off each time; after the last burn- ing plunge into water and cool preparatory to polishing. To temper engraver's diamond point tools, heat to nearly white heat and stick the tool into sealing wax until cool, then dip point into oil of turpentine. To temper common flat, cape or side chisels and flat drills. Shape them ready for the grind- stone, then heat the points about two or three inches back to cherry red and plunge point into luke warm water, leaving the black part warm to drive out the temper to the point, polish point with sand and watch results. When proper temper is attained, plunge whole tool into cold water. Colors : For chipping or drilling cast iron the tools should be dark straw turning to blue. Color for steel and iron should be pretty near blue, and softer than for cast iron. 150 To join a band saw when broken: Bevel each end the length of two blades, fasten saw in braz- ing clamp, wet the joint with solder water made of borax rubbed on slate with water, place piece of silver solder in joint full size and squeeze together with red hot tor»gs. When solder fuses throw water on tongs and cool while holding the joint. Hammer saw if necessary and draw file down to proper thickness. To renew worn files : thorougly cleanse them from grease or oil with alkali, then dip them in a solution made with one part nitric acid, three parts sulphuric acid, seven parts water by weight ; time, five seconds to five minutes, ac- cording to fineness of cut. Wash in hot water, dip in lime water, dry and oil them. To inscribe metal : cover the part with melted beeswax; when cold, write what you desire plainly in the wax clean to the metal with scri- ber, then apply a mixture of \ oz. nitric acid, 1 oz. muriatic acid, with a feather, carefully fill each letter ; let it remain from one to ten min- utes according to appearance desired, then throw on water to stop the process of cutting^ heat wax to remove it, and you have your name. To draw an ellipse, such as man-holes and hand-holes. This can be done by means of a string, pencil and two pins. First lay two lines 151 eauii crossing the other in the middle; these lines to represent the length and breadth of the figure mark the ends of lines A, B, C, D, and then divide the major axis A, B into eight parts, and fix two pins at the divisions, one and seven, as per cut, now fasten one end of a string to 7, and stick a temporary pin at D, pass the string around it and make the string fast to the pin at 1 3 then remove the temporary pin, put the point of a pencil, as x, inside the loop and describe \ the ellipse, then shift the position of the string to the other side of the line A, B, and describe the other half. To make a square or. erect a perpendicular line from any point in a straight line. Let the point C on the straight line A, B, be the one at which it is required to erect a perpendicular. 152 Now, to do this, set one leg of a pair of dividers at C, and then open them to any convenient dis- x -B X tance, say four or twenty inches, C, a, b, put point of dividers at small a, and cross about where the perpendicular should stand, then strike another from where b is, and where the two arcs cross join with C, and the perpendicu- lar line will be the square with parallel line (45 degrees.) 153 Rule to find CIRCUMFERENCES; Multiply the diameter by 3.1416. To find the diameter: Divide the circumference by 3.1416, also find the diameter by multiplying the circumference by .31831. Size. Cm. Size. ClR. Size. ClR. i .3926 10 31.41 30 94.24 \ .7854 i 2" 32.98 31 97.38 I 1.178 11 34.55 32 100.5 i 1.570 J 36.12 33 103.6 5 8 1.963 12 37.69 34 106.8 3 4 2.356 i 39.27 35 109.9 i 2.748 13 40.84 36 113.0 1 3.141 J 42.41 37 116.2 i 3.534 14 43.98 38 119.3 1 3.927 J 45.55 39 122.5 3 8 4.319 15 47.12 40 125.6 § 4.712 i 48.69 41 128.8 1 5.105 16 50.26 42 131.9 i 5.497 i 51.83 43 135.0 7 5.890 17 53.40 44 138.2 2 6.283 i § 54.97 45 141.3 i 7.068 18 56.54 46 144.5 i 7.854 i 58.11 47 147.6 f . 8.639 19 59.69 48 150.7 3 9.424 i 2~ 61.26 49 153.9 i J 0.21 20 62.83 50 157.0 1 2 10.99 J 64.40 51 160.2 5. 4 11.78 21 65.97 52 165.3 4 12.56 J 67.54 53 166.5 i 2 14.13 22 69.11 54 169.9 5 15.70 J 70.68 55 172.7 i 17.27 23 72.25 56 175.9 6 18.84 J 73.82 57 179.0 i 20.42 24 75.39 58 182.2 7 21.99 i f 76.96 59 185.3 i 2 23.56 25 78.54 60 188.4 8 25.13 26 81.68 61 1W1.6 i 26.70 27 84.82 62 194.7 9 28.27 28 87.96 63 197.9 £ 28.84 29 91.10 64 201.0 154 HEIGHTS AND MEASURES TBOT WEIGHT. 24 grains * Pennyweight (dw*.* 20 pennyweights 1 ounce (oi.) 480 grains. 12 ounces 1 P° und « b -> 6760 gramSl 1 scruple. 20 grains • 3 scruples * ° ran > 60 « ram8 ' 8 drams * ounce 48 ° e ™™: 12 ounces 1 P° und 5760 « raIB8 ^ AV0IBDUP0IS WEIGHT. ldram. 27.34375 grains 16 drams 1 °» nc ° «** B™™' lOounces 1 P ound 700 ° * r " ng ; 28 pounds l ^ a f er (q ^ 4 quarters 1 hundredweight (cwt.) 112 pounds. 20 hundredweight 1 ton (T) 2240 pounds. V. S. LIQUID MEASUBE. 4rill8 lpint(pt) 28.875 cubic inches. 2 p int s ...'.'. 1 quart (qt.) 57.750 cubic .nches 4 quarts.':::;.'.::.'.'.'.. i *no» («*•> ^ ** io ™*°\ P gallons 1 "Ogshead (hhd. hogsheads -^JW 2 pipes *'"" U. S. DEY MEASITBE. „ „ ints 1 quart (qt.) 67.2006 cubic inches, 4 quarts':::::.'.'.'.'.::'.'.'.'. i &** ^-) « p*. 268.8o 25 «.» inch-. 2 gallons 1 peck (pk.) 16 pts. 8 qts. 537.605 cubic inches 4 pecks 1 bushel (bush) 64 pts. 32 qts. 8 gals. 2150.42 cubic inches. LONG MEASITBE. 1 foot (ft.) f f !"' :r.'.'.'.'Z.'.'.'."...l yard (yd.) 36 inches. X ■■" 1 rod (rd.) 16>^ feet. IZlZ :Z:::::.'.'.l'fur'long(fur.) 220yards 660 feet. f fu °, on : s ' ::::: i^w awn.*, im^ «»>&<*. 3mUes.':.:.....neaguel.) 960 rods 5280 r ds 15840 feet. 155 PROPERTIES OF SATURATED STEAM. i3 *£ "2 JL d Pressure. d Volume. © O eS dM 5-i . ^, O d '3 5 ® ° 2 ® » 3^ © * S 3 © ,d © o*"" cj u ©* £»-» fe © j- By ^ © h, Com- Cubic feet of ,, © r* rt W . tsts 3 » ©2 Steam Total © rt © is* pared with Steam from e? J3 © © u u, - -T- Guage © — water. 1 lb. of water. ^ 'ota Si tea 2 d tan eat fc-i -moc co oD^a 15 212.0 1642 26.36 965.2 1146.1 5 20 228.0 1229 19.72 952.8 1150.9 10 25 240.1 996 15.99 945.3 1154.6 15 30 250.4 838 13.46 937.9 1157.8 20 35 259.3 726 11.65 9316 1160.5 25 40 267,3 640 10.27 926.0 1162.9 30 45 274.4 572 9.18 920.9 1165.1 35 50 281.0 518 8.31 916.3 1167.1 40 55 287.1 474 7.61 912.0 1169.0 45 60 292.7 437 7.01 908.0 1170.7 50 65 298.0 405 6.49 904.2 1172.3 55 70 302.9 378 6.07 900.8 1173.8 60 75 307.5 353 5.68 897.5 1175.2 65 80 312.0 333 5.35 894.3 1176.5 70 85 316.1 314 5.05 891.4 1177.9 75 90 320.2 298 4.79 888.5 1179.1 80 95 324.1 283 i.55 885.8 1180.3 85 100 327.9 270 4.33 883.1 1181.4 90 105 331.3 257 4.14 880.7 1182.4 95 110 334.6 247 3.97 878.3 1183.5 100 115 338.0 237 3.80 875.9 1184.5 110 125 344.2 219 3.51 871.5 1186.4 120 135 350.1 203 3.27 867.4 1188.2 130 145 355.6 190 3.06 863.5 1189.9 140 155 361.0 179 2.87 859.7 1191.5 150 165 366.0 169 2.71 856.2 1192.9 160 175 370.8 159 2.56 852.9 1194.4 170 185 375.3 151 2.43 849.6 1195.8 180 195 379.7 144 2.31 846.5 1197.2 This table gives the value of all properties of saturated steam required in calculations connected with steam boilers. 156 AREA OF CIRCLES. To find the area of a circle, square the diameter and multiply by .7854. Size. Area. Size. Area. Size. Area. Size. Area. Vs 0.0123 10 78.54 30 706.86 65 3318.3 % 0.0491 % 86.59 31 754.75 66 3421.2 % 0.1104 11 95.03 32 804.24 67 3525.6 y 0.1963 y 103.86 33 855.30 68 3631.6 % 0.3067 12 113.09 34 907.92 69 3739.2 % 0.4417 % 122.71 35 962.11 70 3848.4 % 0.6013 13 132.73 36 1017.8 71 3959.2 i 0.7854 y 2 143.13 37 1075.2 72 4071.5 Vs 0.9940 14 153.93 38 1134.1 73 4185.3 y* 1.227 % 165.13 39 1194.5 74 4300.8 % 1.484 15 186.71 40 1256.6 75 4417.8 y 1.767 y 188.69 41 1320.2 76 4536.4 % 2.073 16 201.06 42 1385.4 77 4656.0 % 2.405 X 213-82 43 1452.2 78 4778.3 % 2.761 17 226.98 44 1520.5 79 4901.6 2 3.141 H 240.52 45 1590.4 80 5026.5 % 3.976 18 254.46 46 1661.9 81 5153.0 y 4.908 x / 2 268.80 47 1734-9 82 5281.0 % 5.939 19 283.52 48 1809.5 83 5410.6 3 7.068 K 298.64 49 1885.7 84 5541.7 & 8.295 20 314.16 50 1963.5 85 5674.5 y* 9.621 H 330.06 5l 2042.8 86 5808.8 % 11.044 21 346.36 52 2123.7 87 5944.6 4 12.566 y 363.05 53 2206.1 88 6082.1 X 15.904 22 380.13 54 2290.2 89 6221.1 5 19.635 y 397.60 55 2375.8 90 6361.7 y 23.758 23 415.47 56 2463.0 91 6503.8 6 28.274 y 24 433.73 57 2551.7 92 6647.6 % 33.183 452.39 58 2642.0 93 6792.9 7 38.484 y 471.43 59 2733.9 94 6939.7 y 44.178 25 490.87 60 2827.4 95 7088.2 s 50.265 26 530.93 61 2922.4 96 7238.2 y 56.745 27 572.55 62 3019.0 97 7389.8 9 63.617 28 615.75 63 3117.2 98 7542.9 % 70.882 29 660.52 64 3216.9 99 7697.7 157 MISCELLANEOUS. Paints, Calcimining, Stains, Colors, etc. — - Soak one pound of white calcimine glue in enough water to cover it, over night; then dis- solve in boiling water, add twenty pounds of whiting diluted with water until the mixture is of the consistency of cream. To this any tint can be given that is desired. TINTS. Lilac — Add to the calcimine two parts of Prussian blue and one of vermillion, stirring thoroughly and taking care to avoid too high a color. Gray — Raw umber with a small amount of lampblack. Rose — Three parts of vermillion and one of red lead added in very small quantities until a delicate shade is produced. Lavender — Mix a light blue and tint it slightly with vermillion. Straw — Chrome yellow with a touch of Spanish brown. Buff — Two parts spruce or Indian yellow and one part burnt sienna. WOOD STAINS. Mahogony — Boil one oz. extract of logwood and two ozs. fustic in one quart of water; 158 brush the wood with this, then go over with a weak solution of potash. Black — Dissolve one oz. extract of logwood in one quart of water; wash the wood with the solution. When dry, wash in vinegar in which rusty iron has been steeped for several days. Golden Yellow — Put % oz. powdered turme- ric in five fluid ounces alcohol in a closely stop- pered bottle, let stand a week in a warm place, shake it occasionally, then strain off clear. Black Walnut — Scald }£ pound burnt umber in one pint of vinegar; strain, and apply with a sponge, when dry rub hard; repeat the staining until sufficiently dark. Walnut No. 2 — Asphaltum thinned with tur- pentine produces a splendid imitation of the natural wood. It must be varnished after staining. Walnut No. 3 — Very thin sized shellac, one gallon; dry umber, burnt, one lb,; rose pink, y 2 lb.; Vandyke brown, burnt, ^ lb.; mix, let stand a day, then stir up and apply with a sponge. Orange — Put one ounce turmeric and a drachm of gum tragacanth in a pint of alcohol; shake well, and after standing four days, strain. Red — Two ozs. potash and two ozs. Brazil wood in one quart of water; let stand in a warm 159 place a few days, stirring occasionally; heat to a boiling point, and apply. Double the quan- tity of potash (four ozs. ) will give a brilliant rose color to the wood. Cherry, on white wood or pine — Alcohol, one quart; ground turmeric, three ozs.; raw gamboge,- \y 2 ozs. Mix well, strain through fine muslin, apply two coats with a sponge, rub down well, and varnish. Antique Oak — Walnut oil, obtained of the druggist, if mixed with the filling applied to red oak or white oak, it will produce the an- tique effect so much sought after and used on furniture and interior finished houses. Quantity of paints, material required for priming, if tinted white lead is used, it will take twenty pounds of lead and five quarts o* raw linseed oil. For second coat, twenty pounds of lead and one gallon of oil. If three- coat work is in- tended, the amount of material required for priming and completing the work will average fifty pounds of lead and 2^£ gallons of oil. To measure painting in square or 100 feet, allow five lbs. of lead one quart of oil. It takes already mixed paints one gallon per coat for each 25 square yards. All should learn how to mix and apply 160 paint. Often at your leisure you can apply your time profitably about your home or en- gine room to beautify the looks and value of the property. When to Paint. — Paint in the fall, winter or early spring, as paint at that season dries slowly and makes a hard, glossy surface. Brushes. — The character of work done wil] determine the kind of brush to use. One or two flat and three round brushes of various sizes will be sufficient; wire bound ones are the most durable. After use, the brushes should be thoroughly cleaned with turpentine and covered with tallow. House Painting. — If the house be new, the knots should be covered with shellac to prevent the rosin from running and discolor the paint, The first coat is white lead and raw linseed oil; boiled oil and turpentine are used in after coats. For inside finish, equal parts of boiled oil and turpentine are used for the second coat, and nearly all turpentine for last coat. The color desired should be in the last coat, the first being pure white lead. Harmony of Colors. — Care should be taken not to use the colors that would give an un- pleasing effect to the work. Common White Paints. — Mix white lead 161 with linseed oil, bringing to the consistency of paste; then add one part turpentine to three parts oil to right consistency. Milk Paints. — Mix water lime with skimmed milk to a proper degree of consistency, to be applied with a brush. It will adhere to any- thing where oil paint has not been used or ap- plied, and is as durable as oil paint. Colors dissolved in whiskey may be added if desired. Compounding Colors. — Any number of shades of colors may be made by mixing other colois. The following shows how to produce some of the most popular shades : Flesh color is made with white lead, lake and vermillion. Cream color is chrome yellow, Venetian red, white lead and red lead in oil. Buff is French yellow, chrome yellow and white lead with tinge of Venetian red mixed in oil. Violet — Vermillion, blue black and little white. Dark Red — Mix Venetian red in boiled oil, little red lead and litharge. Orange — Red lead and French yellow linseed oil. Black and Green. — Durable and cheap black paint is made by grinding powdered charcoal 11 162 in linseed oil, with a little litharge as a drier. Add yellow ochre to this and an excellent green is obtained which will not fade. Cheap Paint for Out Buildings. — Lime, one bushel, and water to make a whitewash; min- eral paint, fift^ lbs.; road dust, fifty lbs.; add oil till it makes a paste, and thin with sweet milk. Cheap Oak Varnish. — Boiled oil, two quarts; litharge, y 2 lb.; shellac, ^ lb.; gum, one oz.; boil till dissolved, then cool, and add two quarts of turpentine. Good Liniment for Man or Beast. — Take % oz. turpentine, y oz. tincture of aqua lauda- num, y 2 oz. oil of sassafras, y 2 oz. hemlock oil, two ozs. tincture myrrh, one oz. oil of ori- ganum, y oz. oil of wintergreen, one oz. chlo- roform, one oz. camphor gum. Mix and apply externally to parts affected. Highly recom- mended for rheumatism, sprains, bruises, swellings, etc., on man or beast. Apply twice a day with naked hand; rub thoroughly. Indelible Ink. — Aniline black, one drop; concentrated hydro chloric acid, six* v y drops; alcohol, y oz. Mix and add 1^| oz. gun. arabic difgol^ed in six ozs. soft water. Liqaid Gla2. — Dissolve good hard g_ue in nifcris 3$Hi@gr. The ether will only take up a 163 certain amount of the glue, so it will not thicken. If small bits of India rubber be added it will resist dampness. The Use of Exhaust Steam for Heating Purposes. — Steam users and engineers have long been interested in the advantages to be derived from the utilization of the exhaust steam from engines or steam pumps, instead of wasting it into the air. By using it as a source of heat to warm manufactories, buildings, etc., and for certain manufacturing processes re- quiring heat, a large percentage of the thermal value of the fuel consumed in boiler furnaces, which is ordinarily lost, is utilized, thus insur- ing economy in fuel. The exhaust steam as it comes from the engine at a little more than 212 degrees Fahr. can be, and is used, to some ad- vantage and economy under certain condi- tions, but experience has shown that owing to its low temperature, moist condition and com- parative slow velocity, it is less efficient for '.he purpose of conveying and radiating heat than steam of a higher temperature; that is dable to sudden and rapid condensation, and Sat it is difficult to obtain a free circulation for heating purposes which eventuates in back pressure on the engine, neutralizing its value by reason of the extra fuel required to enable 164 the engine to carry the extra load. The limit of fair economy in use of exhaust steam is two to three pounds back pressure; beyond this, use live steam to assist in circulation. A re- heater through which the gases pass after leaving the furnace is a valuable improvement in exhaust steam heating; about one hundred degrees of heat is imparted to exhaust steam without interruption of draught or extra ex- penditure of fuel by means of the heat that would otherwise go to water. Chimney gases have a temperature of 400 to 600 degrees, while that of exhaust steam is about 212 de- grees. The economy of this method is there- fore evident Heating Feed Water. — Trujs is a very im- portant department of the steam plant; the feed water supplied to steam boilers has to be heated from the normal temperature to that of steam before evaporation can take place, and this is generally done at the expense of the fuel which should be utilized in making steam. The pressure at 75 pounds is 320 degrees heat; taking 60 degrees as the average temperature of feed we have 260 units of heat per pound, which, as it takes 1151 units to evaporate a pound from 60 degrees, represents a loss of 22;^ per cent of fuel. AH of this heat, there- 165 fore, which can be imparted to the feed water is just so much saved, not only in cost of fuel,, but in capacity of boiler. All heat imparted to feed water by injection and "live steam heaters" is taken from the fuel and does not represent any saving. There are two sources of waste heat avail- able for this purpose — exhaust steam partially used and chimney gases. CORLISS ENGINE. The valve gear of Corliss engines are easily set, when one knows and understands a com- mon slide-valve, as the four valves of a Corliss engine represent the two steam and the two exhaust edges of a common slide-valve. To set the Corliss valve, take off the back valve and exhaust valve chest heads. There will be found marks to set by. See that the wrist plate and four valves are connected and centrally covering their respective ports, that the crank-pin is at dead centre, and the eccen- 166 trie (heavy side) perpendicular. Move the eccentric the direction the engine is to be run and show by the valve chest marks and the edge of valve 1-16 lead (or opening) tighten /he eccentric, and move the crank-pin to the other dead centre, and notice if the other steam valve has the same lead; if equal, the steam valves are O. K. ; if not, make the adjust of Yz it is out, by the connections between the wrist plate and valve. Give the exhaust valves double the lead of steam valves. To adjust the governor' rods or tripping cams, move the wrist plate to one extreme of its travel, adjust the rod connecting with cut-off cam on opposite steam valve, so cam will clear the steel 1-32 of an inch; then do the opposite valve the same. To equalize and test their correctness, hook in the engine with eccentric reach-rod and block up the governor about \% inches, or about the average position the gov- ernor will be in when running; then have some one move the fly-wheel in the running direc- tion, and take notice how far the crosshead (from dead centre) has traveled when the valve unhooks; if the two valves unhook at the same distance from either dead point the cut-off is equal; if otherwise, make adjustments and bring it so they will cut-off equal. 167 AUTOMATIC GOVERNORS. The governors on automatic engines are connected to the eccentric and fly (or balance) wheel, and so connected by means of levers, weights and springs, as to shorten the stroke of the eccentric and valve when engine has attained the proper speed at which it is set. The springs are set before leaving the work- AUTOMATIO ENGINE. shops, and should not be tampered with unless to change the engine to a slower or higher speed. When an engineer wishes to do this he must adjust each spring and weight equally to a hair, or the engine will pound and run un- even. Each builder of automatic engines sup- plies each engine with a book of instructions having therein de c oriptive cuts of valves; movements, etc. 168 ELECTKICITY. In this part of the book we will place in questions and answers the explanation of the dynamo, electricity, etc. Q. What is the cause of a thunder storm or lightning ? A. The common conception of a thunder and lightning storm is that when clouds charged with the sun's potential energy, called electricity, approach and set up an inductive circuit to the earth, the earth forms the oppo- site condensing plate, and if the earth has the least resistance when the tension rises to a degree greater than the resistance can sustain, then the discharge will be from the clouds to the earth in a flash of fire, called lightning (or thunder bolt) the thunder is caused by the rush of the air together after being burnt out by the lightning. Q. Give the different measurements used in electricity? A. The "Volt," which is the unit of measure, known in dynamic terms as "Pres- sure." The "Ampere" is the measure of electricity or amount of current passed, or the amount transmitted or used. The "Ohm," called the resistance. The "Coulomb," called 169 foot pounds or a measure of current. Thje^ "Watt," called the 746th part of an electrical horse power. Q. State as near as you know the force of a thunderbolt? A. The pressure would be about 3,000,000 volts, and about 14,000,000 am- pers used and power, about 2,000,000,000 watts, and the time for all about a twenty - thousandth part of a second. Q. What is a magnet? A. A magnet is anything that will attract and draw to it steel. Magnetism will produce electricity, and vice versa. This is the reason we can do so many wonders through the use of electricity. Q. How would you make a magnet ? A. Take a steel horse shoe and wind it with fine copper wire, starting at one end of the shoe and wind around until we come to the other end of the shoe, and attach the two ends of wire to a battery, and the amperes of electricity will travel through the wire and charge the steel horse shoe with electricity, making of it what is called a magnet. Q. Can you make a magnet out of a soft iron shoe? A. No; not a permanent one, although the iron shoe makes a stronger magnet while the current of electricity passes through it, but as soon as the current ceases, the electricity leaves the shoe. Q. How should a building be protected against lightning? A. As a rule the conductor or lightning rod, as the electricians term it, is supposed to have a sort of power to attract the alectric current or toolt to the ground, like U gutter pipe would carry water from the roof. Q. Is a house safe with them on? A. If enough of them are placed about the house top they may help, say one to every ten square feet. Q. Is atmospheric electricity very dangerous or powerful ? A. It is about the same as the electricity we use for lighting purposes, and is detrimental to telephone, telegraph and other wires carrying low potential currents, also people of a nervous temperament. Q. How should a lightning rod be at the the base to do any particular good* if any, and what is a practical thickness? 171 A. The wire or rod should be at least \ inch, and a solid rod having continuous metallic con- nections. The connection to the ground should be water, moist ground or gas or water pipes, the "bolt" rests and loses its force when it reaches the ground. THE DYNAMO. Q. Explain how you understand a dyamo and its use? A. The dynamo is an electric machine which 172 is driven with a steam engine or water power, and is used to produce the electricity for elec- tric lighting, electroplating, power, etc. This is where magnetism makes electricity. Q. Explain the dynamo? A. The dynamo is a combination of different parts so connected that when in working order it produces electricity, the combination consists SKELETON DYNAMO. of twelve different parts, five of them constitute the magnet, namely: two "cores," K, L, two bottom cores or plate pieces, P, P, and one yoke C, The cores are hollow and wound with wires F, F, the amount is according to the use to which the dynamo is to be put. The poles are called the North and South poles ; herewith will be found skeleton cut of magnet. 173 Q. State the amount of pressure or voltage there is in a dynamo for arc lighting? A. There is about from 2,400 to 3,000 volts, Q. State the amount of voltage on an incan- descent dynamo? A. It is about 110 volts, which is not consi - 6red dangerous and is sufficient for any number of sixteen candle power lamps. Q. Give a description of an arc light? A. An arc light consists of a frame work, clock work, feeder on top, two carbon holders, and two carbons, wir- ing, etc. Q. Why are two carbon pencils used? A. If no resistance was given to the lamp or electri- cal current, we never would have a light. The current passing from one carbon to another breaks off a fine shower of carbon dust from the upper pencil as fine as flour and causes them to reach a white heat, the ends of carbons being hot, to- gether with the shower of carbon dust at white beat makes the light. 174 ^MATURE. 175 Q. Give an illustration of this. A. To illustrate this, take a rope tightly in your hand and let some one pull it quickly through and it would heat, viz : the resistance your hand gave the rope is what causes the heat, therefore the resistance the carbon stick: give the electrical current, causes the immense heat and does as steted in the answer before this one. Q. For what purposes are arc lights used? A. They are used for street lighting, also stores, etc. The armature rests in two journal box stands, on the armature is a commutator made of pieces of isinglass (or insolation) and copper ; the cop- per is connected to the wires on the armature, and on each side of the armature rest two or more brushes two make the circuit complete. Q. Are dynamos permanent magnets? A. No, they are made of cast iron, except the copper and insulation, and as soon as the dyna mo has stopped, the magnetism is a mere noth- ing ; if the dynamo was made of steel it would retain the magnetism and the magnetism could not easily be regulated, where on the other hand the magnetism in the cast-iron dynamo oan be easily regulated. 176 Q. Are there other electric lights besides the arc light just mentioned? A. Yes; the incandescent lamp, which is shaped like a pear, it ie made of thin clear glass, has a U shaped carbon in the glass which is made air tight containing a vacuum. Q. Does the elec- trical current have to jump from one carbon to the other in an in- candescent light the same way as in the arc light ? A. No; the incan- descent carbon is a continual carbon and is about as large as a horse's hair, the car- bonis made of carbon- ized bamboo cane it i? j joined inside by plat- I inum and two thin cop- per wires, one being attached to a brass ring and the other to a brass button at the bottom of the lamp. These 1gm me separated generally by plaster m of paris which is a nonconductor and no elec tricity will pass through it. The struggle between the electric current and the carbonized bamboo is so great and the carbon being the weaker of the two, has to submit to being heated to a white heat, which produces the light. Q. State why it is that the carbon is not wasted as in the arc light? A. Because the one, (arc light) is out in the atmosphere, while the other is heated in a vacuum. Q. How long is the life of an arc light carbon, also an incandescent carbon. A, The arc light (top) carbon will last about from ten to twelve hours and the lower one about twenty or thirty, the lower burns the slowest. In an incandescent globe it never wastes away as the vacuum (which means the exclusion of the oxygen air) prevents it. They (incandes- cent carbons) have lasted from one minute to 1500 hours, just as they are handled and used. Q. What is a switch and its use? A, There are many makes and kinds of switches, some for lamps, some for circuits, such as to cut out the lights in one room and leave another burn 3 or turn out ten lights or any num- ber by switching off each separate light. A switch is a connection between two wires, which circuit can be broken at any time without doing 12 178 any particular harm to anything or anyone. Q. Is there any danger of being shocked with an electric wire? A. If the wire is insulated there is no danger of getting hurt, but there is if not covered, and you are. standing on damp ground, as damp ground and water are great conductors of elec- ARC DYNAMO. tricity. If a man were to take hold of the bare wires used on street car lines and get hold with his feet clear of anything connected to the ground, the current would pass through him and not harm him but if his feet were to touch any- thing connected to the ground his life would pay the penalty, 179 THE MOTOR. Q. Of what use is the electric jpower ? A. It is one of the finest, cleanest and most convenient powers we can pat to use for different purposes, such as driving different machines, sewing machines, printing presses, small fac- tories, street cars, railway trains, etc. ELECTBIC MOTOR. Q. How is this kind of work done by electricity? A. It is done through an electro-motor. (Motor) 180 Q. What is an electro-motor. (Motor.) A. A motor is practically a dynamo machine Q. Is the motor wound the same as a dynamo? A. Yes ; the dynamo is run by an engine and produces the electricity, while the motor gets its power from the Synamo. Q. How does the dynamo deliver its elec- tricity to the motor? A. The dynamo delivers its electricity to the motor through two main wires, which are at- tached, one to each brush of the motor, thus making the driven dynamo a motor. Q. Is the centre of the armature of the mo- tor the same as the dynamo? A. Not exactly, the principle is the same only the spool is made of iron plates fastened together, making one solid piece. Q. What is meant by positive and negative? A. It means North and South poles. The pos- itive will not attract a positive, nor the negative attract a negative, a positive and a negative must always be together to do the work, on a motor armature there are crossed pieces of iron, two negatives and two positives, the magnet is posi- tive and negative, one on each side of the crossed pieces of the armature, therefore the positive magnet draws the negative pieces on the armature 181 and the negative magnet draws the positive and so it keeps on. This is what turns the armature around, the more electricity that is transferred from the dynamo to the motor the faster the motor armature will revolve. Q. What has that to do with moving the wheels of a car, or the moving of machinery ? A. For moving»or running machinery, there is a pulley wheel on the end of the armature of the motor for a belt. For the car motor there is a strong toothed gear wheel which works com- pounded by more wheels moving or turning the axle and wheels of the car. Q. How is the current of electricity conveyed from the overhead wire to the motor ? A. The electricity is conveyed by what is known as a trolley; attached to the trolley wheel is a wire leading down along side of a pole, through the inside frame of the car and to the motor brushes. Q. How is the car stopped or started? A. On each car is a motorman who attends to that part of the car, and the turning on and off of the current is done by a switch under- neath the car, the switch is attached to a link chain, the chain is attached to an upright rod and pinion wheel at the end of the platform. The motorman when he wishes to start or 182 stop the car, turns a small crank handle which opens or closes a switch, whichever he wishes to do; of course, in stopping he uses the brake the same as on any other car. SPARKING OF COMMUTATOR. Q. State the main causes of the commutator to spark? A. Brushes not being properly or evenly set with the centre line on the commutator, bad in- sulation on the armature wiring, grease and dirt in the brushes coming in contact with the arma- ture, also too much of the surface of brush cov- ering the commutator,, Q. How would you find the trouble ; state by the color of sparks ? A. If the brushes are too short the color is generally a greenish color, if the spark sputters or has a reddish color the brushes are too long, badly worn or have had too much contact; this causes the eating away of the commutator, Q. If this is not prevented what will be the result? A. If not attended to, the edges of the cop- per segments of the commutator will be eaten away and the commutator will become as rough as a piece of corduroy cloth. Q. What will copper dust o^ oil do on a commutator ? 183 A. It will carry the fire all trie way around the commutator, Q. Is this the only cause of such a spark? A. No; sometimes it will be found near the spot that the insulation is charred or one of the connections between the armature wires and the copper segment of the commutator is loose or bad. Q. What is the result or cause of this? A. A short circuit. Q. In what condition does the face of the commutator look near or in line of this spark? A. It leaves a flat or hollow spot, such as could be made with the pene of a hammer. Q. What should be done when a spot is found like the one mentioned? A. Dress the commutator down to a round smooth surface. Q. State a good way to keep a brush from wearing out too soon? A. A good way is to turn the brush over. Q. What causes a hot commutator ? A. Generally badly worn and dirty brushes. Q. With what can a dynamo be compared so as to be easily understood? A. If an engineer wishes to understand the dynamo thoroughly he should compare it with the workings of a steam pump. Q. Give an explanation of the pump theory? 184 A. The dynamo or pump gathers electricity and forces it through the wires, the same as a pump does water through a line of pipe, except that the dynamo forms a complete circuit from the dynamo out and returns to the dynamo whereas the pump forces in one direction or line, but if the pump forced the same water contin- ually by having it flow back to the pump again its comparison would be with that of the dynamo. Q. What else can be compared? A. We can compare the steam pressure which overcomes the resistance or friction of the water in the pipe, with the voltage cf the dynamo to overcome the resistance of the wire and carbons. Q. With what would you compare amperes? A. The amount delivered. Q. With what would you compare the line- wire? A. To the water pipe. Q. With what would you compare the current? A. Compare the current to the amount of water in motion, Q. Suppose the dynamo was large and the wire small what would be the consequence or comparison? A. The smaller the wire the more relative friction or resistance to the number of amperes delivered and the larger the main wires leading 185 from the dynamo the less relative friction or re- sistance in delivering the number of amperes, and current of electricity. Q. What is meant by a converter on an al- ternating system? A. It means in engineering a reducing value, or carrying a high voltage at the dynamo and passing through the converter the voltage is re- duced for the lamps, Q. What is an alternating dynamo? A. It is a high voltage or arc machine using a converter (just explained) to which incandes- cent lights are attached. Q. What is meant here by a continuous cur rent of electricity ? A. It is understood that it is a current that flows in one direction, like steam in a pipe or water in a hose. Q. What is meant here by an alternating current, also compare it to something? A. Compare it to the crank and connecting rod; no dynamo or electric generator yet invented designed or made, ever did generate anything but alternating currents of electricity, or more correctly speaking waves or impulses of potential. Q. How is the alternating current cummuted into a continuous current ? A, It is done by the commutator and jrushes; 186 therefore the alternating is the original and only, and the continuous currents are obtained from any machine by manipulating the original or alternating current. Q. What is the horse power of a continuous current dynamo the voltage being 110 and am- peres 330? A. The voltage being 110 and the amperes 330; we multiply 330 X 110 = 36.300 watts, and as 746 watts equal one horse-power, we divide 36.300 -T* 746 = 48 horse power. In continuous current engineering, the resistance of the wire is about all the obstruction that has to be calculated but in alternating circuits another factor comes in that of inertia, or self induction Indepen- dence depends directly upon the resistance of the conductors, and the inertia of the current in the circuit. If we construct a right angle tri- angle, and let the base equal the number of ohms resistance, then let the upright equal in a similar manner the inertia of self induction of the circuit ; then the level line will be the inde- pendence or total resistance in the circuit. The inertia, or self induction of a circuit is just as great in one used for continuous currents as it is in one for alternating distribution, but as in- ertia only makes itself felt when a body is stopped or started, it is only with the continu- 187 ous current when that is first started and when it is stopped, that is, the electric current tends to hang back when being started, and to keep on moving when we wish to stop it, just as a fly- wheel does. The inertia of a continuous current shows itself when we open a switch through which a heavy current is passing. The inertia of the current prevents its stopping the instant the circuit is broken, and the fine arc often formed across the switch is the " coming along " of current left after the supply was cut off. Electric inertia in any 'conductor depends largely upon the amount of magnets, motors, converters, etc., in the circuit, and it can be ex- perimented with by pulling the fields of a motor or dynamo into a bell circuit. Ring the bell through the coils of wire thus added, and it will be noticed that the bell does not begin to ring as quickly as when the coils are not in circuit. Also that the bell rings a little after the contact has been broken, showing that the current lags behind. Another example, but more of mag- netism than electricity, is in the position of the brushes on a dynamo; they have to be twisted around to fit the lag of the magnetic current. We now come to the term "phase." If we take two alternating dynamos and couple the shafts together so that they are obliged to run 188 at the same speed, then we may say that the alternations of current have the same phase. The highest point or maximum of positive volt- age occur at the same instant in both dynamos, hence the phases of the two machines are the same. Let the two machines be uncoupled and driver separated by belt and we may find that their positive maximums do not come exactly the same time, hence we may say the phase of the two dynamos are different. In other words, we may say that the maximum of positive elec- tro-motive force occurs at exactly the same time in each machine; in any other case, the phases differ. An engineer can get a pretty good idea of the meaning of " phase" by standing in line with the crank shafts of two engines, both of which are running. If both cranks come to their high- est points at exactly the same instant, their phase is the same, but if one of the cranks gradually draws ahead of the other then the phases are different. We have now come to the terms often heard in connection with alternating currents, viz., one, two, three, four phase, etc. If we should take the two engines when they were running with their cranks at ninety degrees to each other, and suddenly couple them together thus, they would be running in two-phase, or bi-phase, like 189 the drivers of a locomotive. That may be called a "bi-phase" engine. If three engines were coupled together with cranks at 120, the com- bination would be called a "tri- phase" engine. An example of this may be found in the naptha launch engines, so well and favorably known. When four engines are coupled together they are called " quadruple," and the coupling of four dynamos follow the same nomenclature. By coupling the engines we get rid of dead points, and raise the line of mean efficiency. The same thing is done in coupling up alternating dynamos, The mean efficiency line is raised, and the dead points are got rid of. TELEGRAPH AND BATTERIES. Q. What is telegraphy ? A. Telegraph means to make known by sound. Q. What constitutes a telegraphers outfit? A The battery, wire, sounder and key. Q. How can one tell by sound the word meant ? A. By dots, dashes and spaces. Q. Of what use is a battery? A. To produce the necessary electricity. Q. Can any one telegraph without electricity ? A. Yes, within hearing distance, but for long distances one hundred feet to any distance in 190 miles electricity and iron wire must be used. Q. State what is a telegraph key? A. A telegraph key is usually made of brass, except the knob upon the handle, which is hard rubber or gutta percha. The second little knob is the switch to close when key is not in service and to let messages pass from one city or station to another on either side of your own, in other words it makes a free passage way for electricity- TELEGKAPH KEY. Q. When should this switch be open? A. When one wishes to send a message. Q. What is meant by a dot, dash and space ? A. To press the key down and let it spring back quickly, that means a dot. To press down the key and hold it there a little bit longer, that is a dash. To wait a little while before pressing down the key again, represents a space. 191 Q. Can you go through the alphabet ? A. Yes, A is a dot and dash : B is a dash and three dots : C is two dots, a space and one dot; D is a dash and two dots ; E is a single dot ; F is one dot, dash, one dot ; G is two dashes and one dot ; H is four dots ; I is two dots ; J is one dash, one dot, one dash, one dot ; K, dash, dot, dash ; L, long dash ; M, two dashes ; N, dash and dot ; O, dot, space, dot ; P, five dots ; Q, two dots, dash, dot ; R, one dot, space, two dots ; S, A B O D E F G HI 3 K £ IT » aaaa aa bessbs ■Bfl^ OBBB BBBB fl** V Q B 8 L T V i a aaaaa ilea m aa bbb aa" iia V W X Y Z & abbbi mmm aaaaa aa aa aaa a a aaf TELEGRAPHIC CODE. three dots ; T, space ; U, two dots one dash ; V, three dots and dash ; W, one dot two dashes ; X, one dot, one dash, tw T o dots ; Y, two dots, space, two dots ; Z, three dots, space, one dot ; &, ons dot, space, three dots. To make the above more plain we have placed the dots, dashes and spaces under each letter so they can b© more plainlj understood. 192 Q. What is a sounder? A. A sounder consists of two black pillars which are iron cases wound with very fine cop- per wire, and is called an electro-magnet, and across the top of the two pillars is a piece of iron representing the armature, held up by a spring. Q. How are the wire key sounder and bat- tery connected with the single wire ? SOUNDER. A. The battery is connected to the earth, the sounder to the battery, the key to the sounder, and the outside wire to the key. Q. What is a battery? A. There are various kinds of batteries, such as the Leclanch's porous cup battery, Law bat- tery, Grenet battery, the Tillotson battery, and several other makes of batteries. Batteries are divided into two classes, "open circuit " and " closed circuit." The open eircuit batteries are used on telephones, electric bells, burglar alarms, gas lighting, annunciators, etc. The closed cir- cuits are for electric lights and motors. LIBRARY OF CONGRESS 028 156 575 8