ZWICKER'S REVISED Practicai Instructor FOR MACHINISTS, FiREAAEN, Electricians, STEAM ENGINEERS. .m }M W^^S, »A\s.^ 'f '/ ''^^^r^^ ^ m^- '/^^^3W^. ^dj ,Kr''^' LIBRARY OF CONGRESS. ©|itp. ...._.;:' ©xrp^riglji fu Slielf.._L2a7 lK9f UNITED STATES OF AMERICA. J Wi ZWICKER'S liEVisi';]). PRACTICAL INSTRUGTOE IN Questions and Answers FOR Machinists, Fireien, Electricians. STEAM EEINEERS. '^^ Br / «V-C*^ Philip Henry Zwicker. Practical Ktiainecr and Ma/:hi}H*t. Copyright iS';ii. WALTER G. KRAFT, CillCAGO. - T ^11 ^3( PRESS OF 281-1S3 South Ci^ark Street, CHICAGO. -T^ %% 6-3^ ;P~ I INTRODUCTION. This book is Aviitten for the special iufonnatioii of Engineers, Macliinists, Firemen and Electri- cians who have to sooner or later procure an engineers license by going before a board of prac- tical engineei-s and answering questions relating: to the care of boilers, pumps, injectors, engines, indicator safetv-valve and electric light dynamo Lefore they can collect their salary as an engineer* It is hoped its pmctical suggestioi^s will enable those who follow them to gain a better insight of the work they have to perform. The real object in writing this book is to help my fellow^ man and not keep him in the dark. All questions are ansAvered in plain and simple language, so any man of limited education can thoroughly under- stand. Very truly yours, P. H. Z WICKER, Author. ZWICKER'S REVISED PRACTICAL INSTRUCTIONS QUESTIONS AND ANSWERS Mdcliiiiists. Firemen, Electriciaiis M Stediii Eoqiiieers Q. Wluit are the duties of an Eugineer? zV. His duties are to take lull charge of the boilers and engines vrhere ever he may be employ • ed, and see that the steam nuicljinery under his charge are kept in No. 1 order with little expense to his employer. Q. What is required of a man to l)tconu: i>. first-class Engineer '? A. He is obliged to obtain an Engineers license tiuu'hmg his qualilications as an engineer of steam c]ininesri)v which will be shown that he is a suitable and safe person to be intrusted with the powers and duties of an engineer. Q. What experience must a man have in order to get his application before a board of Engineers ? A. His experience muatbe generally two years, at mechanical or steam engineering, which must "be sworn to by two citizens, one being a licensed engineer and the other a good reliable citizen, both living in the city, where applicant has worked- QUESTIONS AND ANSWEBS. Q. What business do you follow? A Q. What is a steam boiler, hoAv is it, and of what is it made ? A. A steam boiler is a closed vessel made Of gteel, iron or copper plates, the most in use is J i: '■^lic^ ;o iuch thick, and ranging from 40,000 to 85,000 lbs. tensile strength; these plates are run through a rolhng machine and rolkd in a circle, then riveted together, generally with two rows of rivets, because the strain is greater side- wise than endwise, the seams around the boiler are single riveted because the strain is not so gi^eat; the boiler is braced by different kmds of braces, such as a crowfoot. Longitudinal dome, side,, braces, etc. The eye is riveted to the head ofthe^boiler, which head is generally made of f inch pliite, tlie otlier eye is riveted to tiie side top or dome of Loiler, and tlie brace and eye are put together hv bolts witli a spht key to keep the bolt in its place. Q. Which are the chief points in the construc- tion of a successful and economical boiler? X. Proper circulation facilities constitute one of the chief points in the construction of a success- ful and economical boiler. In tubular boilers, the best practise is to place the tubes in vei*tical TOWS, (phnnb) leaving out what would be the center row. The circulation is up tlie sides of the l)oiier and down the center. Tubes set zig- zajo- or to break si>aces impede the circulation and ^vili not 231'actically give the best results. ' Q. How should a brace fit? A. It should fit tight, for if it were loose it w'ould be of no account. Q. If you found a brace loose, Avhitt would you y jumping it endwise on a Hock of wood until it is tlie proper length. ,Q. AVliy is a boiloi braced ? A. For «t.reiigtli. Q. What is a slay boil? A. A stay lM)lt is a screw bolt, put tlirougli an outside and iiit<^ an inside slieot, so as to hold them tliat they ma}^ not s[)vead or colhipse, «uc]i as a fire-box sheet and an outside shell, they are put together Avith stay bolts so as to allow a water space between the two sheets. Q. How are stay bolts made and put in? A. They ai-e made with one continuous thread, and screwed tln'ough the outside, then through the space between, then througli the iire-box sheet and allowed to stick through -f^ of an inch, so tliey can be riveted over each end to act as a brace, the space between tlie two sheets is called a water space. Q. What is meant by corrosion? A. It means wasting away of the iron of boilers plates by pitting, grooving, etc. There is internal and external corrosion; the acids in and minerals in the water liberated by the lieat, attack the boiler internally, and the sulphur which conies out of the coal has a strong at- tachment for iron, and that attacks the outside. — 8 — Q. How would you find tlie water level when your boiler is foaming? A. The proper -way would be to yliut down the engine and all valves connected with the boiler^ cover fire witli ashes, close the damper, then the water will quiet down, and the level of the water easily found. An engineer should know when lighting a fresh fire, never to force H, but let it heat gradually, so that all parts ex- j)and as near equal as possible; good judgment IS needed. J>oilers and steam guages should be tested at least once a year. Q. Where would you put a steam gauge? A. Sometimes on toj> of the boiler, and in some cases on the steam drum. It must alway.« be tapp«^'d into the steam part of the boiler, the shorter the ])ipe the better. The steam gauge and safety valve sliould coiTespond under all circumstances. Q. Why is a j^et cock put under the steam guage? A. To drain the pipe in cold weather. Q. What kind of a steam gauge have you got? A. A spring gauge. Q. What is a steam gauge for? A. To indicate the preseiu'e in pounds \k'v square inch in the boiler. Q. Does the steam gauge get out of order'/ A. Yes, sometimes. Q. If the steam gauge was out of order what would you be governed by? A. By the safety valve. Q. How would you know tliat it was iu working order? A. By raising tlie lever two or three time* to see that the valve is not stuck. Q. What is a safety ^-alve for? A. It is intended to release the boiler niid prevent explosions from over-pressure. Q. How large should the safety valve be in proportion to the boiler, and grate surface? A. The safety valve should be ^ square ■inch to each square foot of grate surface, which will make it large enough to relieve the boiler of all steam generated over which the safety valve is set. Q. Which.are the better, gauge cocks or glass gauges, and which would you be i^overned by? — 1 — A. G.iug'o coukx, because gla^^s gauges are liable to get stonped with mud, aud not give a true level of the water, but tliey are a very handy thing; they should l>e blown out four oi- iive times a day, so as to keep tliem from clog- ging up. (}. What would you do in case a glass siiould happen to break? A. First close the water valve to prevent the escape of water, close the steam valve, in- sert a new glass, then turn on the steam valve first, the Avater valve next, then close the pet cock at the bottom and everytliing will be all right. Q. What is the best way to clean a glass gauge inside'? A. The best Avay, is to take a small piece of waste and tie it to a strong thin stick, saturate the waste with soap or acetic acid, ])ass down inside of tlie glass, then blow through with steam and the glass will be clean as new. Never touch the inside of a glass water gauge with wire, if you do, it will crack. The best glasses are the Scotch brand, called Eureka. ' Q. If }()ur gauge cock, or a small j'ipe in — 1 1 — tlio large sU'jiui pipe, ^l»oilI(I ]iai)].<'ii to get broken off, ^vliat Avould you do? A. Make a liani wood plug and drive it iir. witli a lieavy hammer, tlieii leave it so until it oould be repaired, by eutting out the old piece, retappiug and putting in another pi}>e or gauge cock, whichever the case may be. Q. Vriiat clearance should a boiler liave? A. It should have from 3 to 4 inches at the fire-line, and from 5 to 1 inches between the shell and bridge wall; a boiler should have from 2 to 3 bridge walls so the iire will hug the boiler; it also makes the coal burn cleaner and s-teams easier. The first bridge wall should be on the back end of the grate bars, and otliers about 3 to 5 feet apart, according to the length of the boiler. Where the smoke returns through the flues, it should be about I larger than the area of liues or tubes combined, bridge walls should lean toward the back. Q. How should a boiler rest and what on? • A. The front end of the boiler should rest on the fire front, and the back end generally rests on a cast iron leg or two or three rollers, — 12 — to allow the boiler to expand equally. Tlie mad dram should always liang free under all circum- stances. Q. In what should engineei-s be careful and exercise good judgment? A. Engineers should be careful in starting or stopping an engine with a high ])ressure of steam. Q. Why should engineers he careful in starling or stopping an engine? A. Because the rent in giving the steam in starting, and the sudden check in stoping, may rause such a pressure as to rupture the boiler. Q. What else should engineers look after? A. Engineers should see that their draft is mot choked by ashes under the boiler, and that the outside of the boiler and inside of Hues }ire kept clean, then they will have no trouble in keeping up steam. Q. How \vould you clean the lines or tabes of a steam boiler? A. By either blowing steam through them or using a flue cleaning brush. Q. How are flues or. tubes cleaned by steam? A. Sonif boilors li.'jvc a 1 .1 itic-li )>ip(" with a valve attached, al^o branch pipes of smaller (limoiisioiis, leading from tlie J^ inch pi[>e into the back end and into the flues; others have a liose attaclied to the front end leading from the steam drum, so the flues or tubes ean be blown out from the front end. (Cleaning bv the brush is the better and more popular way.) Q. How often would you clean out the flues ami when? A. Onee ;i day, in the afternoon, sometime,-^ in the morning after raising steam. (I. What different straijis has a boiler? A. To the flues or tubes it lias a erusliing strain, to the shell a tearing strain. (}. AVh.at causes boiler explosions? A. Thei"c are various causes, such as low water, over-pressure of steam, bad safety \alve, foaming boilers and burnt sheets. (). Why would a foaminu- boiler cause an. (L'Xj)losion? A. It general h" raises the water from the heated sheets. They bv'comc hot; the water falling back on them th'.-y crack, aiui some- — 14 — times cause an explosion. A blistx3red sheet 'or a scaly boiler will also cause an explosion, bj^ allowing the sheets to become burnt and weak €ned; also an untrue steam gauge is very bad. Q. What are the worst explosions V A. The worst explosions are caused by high pressure and plenty of water; low water allows the iron to burn and crack, which weakens it, and when the cold water touches it, it does not take so niucli to burst. Q. riow would you know if your boiler had blistered sheets or was rotten? A. By the hammer test; by taking a small hammer and going inside and outside of the- l>oiler and seeing if it is all right by sound. Q. Mow would you know by sound? A. i]y the different sounds it has; if it rings and sounds solid it is all right; but if it sounds dead, hollow or blunt, there is something wrong. Q. Would you strike the iron hard? A. Yes, pretty hard. Do ))ot hesitate to have a boiler insured, as insurance is generally accom[>anied by hammer test and intelligent inspection, which guaran- tees safety to the engineer or owner. Do not reject the advice or suggestions of intelligent boiler inspectors, as their experience enables them to discriminate in cases which never come under the observation of men who do not follow inspection as a business. Q. If you wished to put a patch on a boiler what kind would you put on? A. A hard patch; it is, reliable and safe. , Q. Why not put on a soft patch? A. Because they are not reliable and are dangerous. Q. What is the difference between a hard and soft patch ? A. A hard patch is a patch where the piece is cut out of the boiler and rivet holes are di-illed or punclied through, then the- patch is riveted on, chipped, caulked aiid made wat«r and steam tight. ? Q. What is a soft patch ? A, A soft patch is put over the plate that needs patching, and put on with -§ or |- inch countersunk screw bt out out for a soft patch as in a liard patch, consequently the patch is burnt, as the water ill the boiler can not come in contact with the patcl). Q. ^Vllicll are the better, driih'*] or nuneht-d holes ? A. Drilled holes. Q. Why ? A. Because the tiller o^ the iron is not dis- turbed as in punching; in drilling, the iron is cut out reguhir; in ]»unching, it is forced out at once . Q. What should be the proper rivets for certain sized siieets, and how far apart ? A. Tlie rivets sliould be -^' and -|- incli diani- eter, and 1^} to -j inches apart. Q. Before sliutting down at night, wiiar, should be iie? A. Pull out the tii"i', punij) up to the third gauge and close the glass gauge cocks, so tlsafc ill case tlie glass should happen to get broken during the night, tlie water could not escape. Q, Wliat ^^■•)uld you do the first tfjing in the morning «hi entering the boiler-room. A. See how mucii water was in the boiler by trying the gauge cocks, then open the glass jrauire valves, and start the fire to raise steam. Q. Why do you try the gauge cocks, and not trust to the glass gauge? A. Because tlie water pipe connecting the glass gauge witli the boiler is liable to become stopped up with mud, consequently the glass would not show a true level of water. The glass gauge should be blown out five or six times a day, to insure safety, but never depend on the glass gauge alone. Q. If you found too much w^ater in the boiler during the day, what would you do? A. Open the blow-ofiP valve and let out water to the second gauge. An engineer should be very careful when blovv^ing out water when he has a hot fire in the boiler furnace, as the water leaves very fast, and may blow out too much ; good judgment should be used. Q. How WH^uld you clean a boiler ? A. First see that there is no fire under thy boiler, then let out all the water throuirh the — 18 — blow-off valve, take out the man, hand, and mud-drum plates ; then take a short-handle broom, a candle or torch, a small hand-pick, a scraper made out of an old file flattened on the end and bent to suit, also a half- inch square iron twisted link chain, about 3 feet long, with a ring at each end to answer for a handle ; place the chain around the flue and work the chain to get the scale off the bottom of the flues; use the ])ick and scraper to pick and scrape oft' all that can be seen on top of the flues and the bottom and sides of the shell ; then wash out into the mud-drum; clean out and put in the mud-drum and hand-hole plates; fill up to top of flues; then put in the man-hole plate, and fill up to the sec- ond gauge ready for raising steam. Q. Could a boiler not be blown out ? A. Yes, but not practically. Q. How much pressure would you allow ? A. About 10 or 20 pounds. Q. Why not more press'.ire? A. Because the heat would be so great that the expansion and contraction would not be equal ; consequently, the boiler seams would — 1 9 — probably leak and the boiler be injured. The better way is no steam pressure. Q. What benefit is gained by letting the water stay in the boiler until you are ready to clean it out ? A. The mud is kept soft and the scale is not caked to the shell or tubes; also, the seams and the boiler are not injured by unequal expansion and contraction. Q. How should man and handhold plates be taken out and put in? A. They should be marked with a chisel at che top, also the boiler at man-hole and hand- hole, whichever it might be, and they should be put in the same way they came out. Q. How would you gasket the man-hole or hand-hole plates of a boiler ? A. With pure lead rings; some use sheet rubber, etc. Q. Why are man-hole and hand-hole plates made oblong instead of round ? A. Because if they were round they could not be taken out or put in, and a man could not easily enter the boiler. — 20 -— ^Q. When filling a boiler v/ith cold water, and raising steam, wliat should be done ? A. A valve should be left open, "^Q. Wiiy do you leave a valve open ? A. Because a boiler fills easier and quicker, and in raising steam the cold air is let out, whicb allows equal expansion, as cold air pre- \^ents equal expansion. "^Q. How would you set a boiler? A. By using a spirit level across and along the flues allowing the end furthest from the ^auge cocks ^ inch lower for every 10 feet ir 3ength. Q. Why ? A. Because v/lien there is water in the gauge cocks, there will surely be water in the other end. Q. How many gauge cocks has a boiler? A. Generally three. ■,.'Q. Where is the first ? A. Two inc-hes above the flues, and the rest two inches apart. Q. Whereis the water line? A. First gauge. <5. Where would ^'ou cai-ry w;iter when runninir'? A. Svcoixl u-nuiL-e. — 21 — Q. Where would you carry water when shutting down at night? A. Third gauge. Q. Why? A. To allow for evaporation and leakage.. Q. Where is the fire line of a boiler ? A. In line or little below^ first gauge. Q. When you open a boiler and look iu„ where do the scales form and lay thickest ? A. Over the fire-plates and around the mud- drum leg or blow-off pipe. Q. Why ? A. Because the circulation and heat are^ greatest there. Q. What is a steam drum for? A. To have more steam in voluinev Q. Which is the hotter, coming out of the same boiler, steam or water ? A. They are the same, only water will re- tain the heat longer, as water is a fluid andi steam a vapor. Q. IIow should the circulation and feed be? y^^. The circulation and feed should be con* tinual. Q. Why ? A. Because boilers have exploded just as-. the steam valve was opened to start the engine, after having stood still for some time. This is generally caused by the plates that are in con- tact with the fire becoming overheated, as the circulation being stopped after the steam is shut off. And just as soon as the valve is opened the pressure becomes lessened, and the water on the overheated sheets flashes into steam of GREAT ELASTIC FORCE, and if the boiler is not strong enough, a terrific explosion is the result, Q. If you tried the gauge cocks and found no water in sight, what would you do? A. Simply shovel wet ashes over the fire pu]l it out, raise the flue caps and let the boiler cool down. Q. Why do you throw wet ashes over the fire before pulling it out? y A. If the fire was stirred up it would create more heat and be liable to burn the plates. The braces in the boiler should be examined to see if they are loose, also the sheets, flues, heads and seams, to see if they are cracked or leaking ; if they are not attended to, they may cause trouble and loss of life and limb. Engi- iieers should not allow anything about the en- gine or boiler room to become greasy or dirty, for it shows poor management, and a careless, worthless engineer. If valves or cocks leak, they should be ground in with emery and oil until a seat or true bearing is found. Ground glass is good for grinding brass valves. Q. When should the boiler seams be caulked ? A. When the boiler is empty and cold, for when the boiler is hot and filled with water, the jarring while caulking would have a tendency to spring a leak somewhere else. Q. Would you call pressure and weight the same? A. No. Q. Why? A. Because pressure forces in every direc- tion, while weight presses down. Q. Which is best, the riveted or the lap- welded flues ? ^ A. The lap-welded flues, as they are a true circle and not so easily collapsed as the riveted iiues. Q. Why? A. Because the riveted flues are not a true circle. — 24 — Q. What is foaming? A. Foaming is the water and eteam mixed together. Q, What causes foaming? A. Dirty, greasy, oily and soapy water; salt water forced into fresh water, also too much water and not enough steam room, will cause foaming. Q. What is priming? A. Priming is the lifting of water with Bteam, such as opening a valve suddenly, and drawing the water from the boiler to the cyl- inder of the engine. Q. What would you do in that case ? y A. Close the throttle valve and leave it closed for a few minutes, then open the valve slowly; that will remedy it. Sometimes prim- ing is caused by too much w^ater and not enough steam room; in that case carry less water. Q. Are boilers sometimes injured by the hydraulic test? A. Yes, if tested by an inexperienced per- son. The hydraulic test is the safest, because if the boiler is bursted no one is likely to get — 25 — hurt. Never use steam pressure under any cir- cumstances for testing. Q. If you had a high pressure of steam, and water was out of sight, would you raise the safety valve to let off the pressure ? A. No, under no circumstances. Q. Why not ? A. Because it would cause the water to rise, and when the valve closed the water would drop on the heated parts and be liable to cause an explosion. Q. If your boiler was too small to keep up the amount of steam required, w^ould you weight down the safety valve to carry a higher pressure? A. No. Q. Why not ? A. Because it would show carelessness and a violation of the law^s. There is no mystery about boiler explosions. They are simply caused by carelessness, and no man has the right to endanger the lives and property of others when he knows that he is incompetent to perform the duty required of him as an engi- neer, whether licensed or otherwise. y Q. How much space should there be between the tubes of a steam boiler? A. The space should be one-half the diam- eter of the tube itself. Q. Can you name the principal valve on a gteam boiler ? A. Yes. The safety valve, by all means. Q. Where should the lower gauge cock be placed in an upright boiler, any size boiler? A. One-third the distance from the top, be tweon tlie two flue sheets. Q. How long a time would you consider it safe to leave the engine room alone without attentioji? A. Under no circumstances should the en- gine or boiler room be left alone. Q. Why not, when everything is in working order? A. Because no man can tell at what mo- ment an accident might occur, which if neglected might cause a serious loss of life and property. Q. What is the boiling point of water? A. It is 212 degrees of heat. Q. At what point does water turn into steam? A. It evaporates at 213 degrees. PUMPS. Q. What kinds of puraps are there? A. There are many kinds, but we consider only single action and double action for feeding boilers and general use. Q. How many valves has a single action plunger pump? A. Two valves, a receiving valve and a dis- charge valve. Q. How many valves has a double action? A. Four, two receiving and two discharg- ing. The double action receives and discharges both strokes. This kind of pump has a steam cylinder on one end. Large pumps have eight, sixteen and thirty-two small valves on water cylinder, according to the size of the pump. Q. Why do large pumps have many small water valves and not a few larger ones in pro- portion? A. The reason the pumps have small valves is that the valves do not have to open as much as larger ones, consequently the pump does not — 28 — loose the quaDtity of water each stroke as it would with larger valves. Q. How are pumps set up and leveled? A. Set the pump so the receiving is from the boiler and the discharge toward the boiler, put in the same size receiving and discharge pipe as tapped in the pump, so the pump can have a good supply and discharge. The pump is leveled with a spirit-level or a square and plumb line. To level a double-action pump, some level across the frame and along the pis- ton; the other way is to take the valve cham- ber cap off the water cylinder and level the valve seats, so the valves will rise and drop plumb. To level a single action pump, take off the valve chamber caps and level both ways. Q. How are the steam valves of duplex pumps set and adjusted? A. Take off the valve chest cover, shove the piston against one of the cylinder heads and mark the piston rod with a pencil at the packing-box gland, tb^" shove the piston against the other cylinder-head and make a another mark, iind the center between the two — 20 — marks andmove the piston until the center mark reaches the packing-box gland where the first mark was made. Or in other words plumb the lever that connects tlie valve rocker shaft and the piston. After this is done, see how the steam valve is for lead; if equal at both ends the valve is set, if not, adjust by uncoupling the valve stem at the coupling outside of the packing box, and turn to suit the adjustment in equalizing the "lead." Q. How is the water piston packed and with what in the water cylinder ? A. It is generally packed with square canvas and rubber mixed packing; it generally takes two pieces; one piece is jointed on top, and the other at the bottom, to make v^^hat engineers call a broken joint. The packing runs from ^ to ^ inch square. These are the general sizes used for common sized pumps. Q. What other valve has a pump near the boiler ? A. A check valve. Q. What is a check valve for? A. To check the water in the boiler from coming back, in case lliere is any work to be done on the pump. Q. Could you pump water into tiie boiler if you had four or five check valves on the dis- charge pipe? A. Yes, I could force throngh all, but it would be more labor on the pump, because the plunger would have to force harder to raise the number of check valves. Q. Where is a pet cock j.ut on the pumjx barrel for cold water, and why? A. It is put at the side and near the bottom of the pump barrel, and is there to sliow how the pump is working, and to drain the pump in winter to prevent freezing. Q. ITow do you know when your pump is in good working order? A. By opening the pet cock and seeing the stream that comes out. Q. How does it show when the pump is in. good working order ? A. Nothing in the suction stroke and full force in the discharge stroke. Q. Where would you locate the trouble if it came full force both strokes? — 31 — A. 1 would locate it at check and discbarge valves, both being caught up. ^ Q. Where would you locate the trouble if it came full force both strokes, moderate, tank or hydrant pressure? A. At the receiving valve. Q. Can you run a pump without a che^tk valve? A. If the discharge valve is in good order, it can; but if there is neither check nor dis- charge, it can not. Q. Can you feed a boiler without a pump? A. If the pressure of the boiler is below the pressure of the feed water or city pressure, it can, by simply opening a water valve and let- ting in the amount of water required. Q. What other way is a boiler fed? A. By an injector or an inspirator. Q. What is an injector or an inspirator? A. They are devices to answer for a pump in feeding a boiler; they draw force and heat the water at the same time. See Page 46. Q. Must a pump have a valve? A. Yes, if a pump had no valve it would not — 32 — do any work. A pump is not r pump unless it has a valve. There are common well hand pumps with one valve, called a receiving or suction valve, but a force pump has two valves, a receiving and discharge ; the discharge is to retain the water after it is delivered, so the plunger can get a fresh supply. After the plunger has ascended and begins to descend, the vrater sets on top of the receiving and under the discharge; consequently, when tlie plunger descends it forces the receiving shut and the discharge open. Q. Should there not be another valve near the boiler ? A. Yes, a globe valve between the check "valve and the boiler. Q. What is that for ? A* To close and keep the pressure in the boiler in case the check valve is cauglit up and needs repairing. Q. Can you raise, lift or suck hot water with a pump ? A. Not very well. Q. Why ? A. Because the pump would get steam bound. Hot water sliould be level o. 'liglier than the pump in order to work well. Q. \Yhere should a pet cock be put on the pump barrel for hot water ? A. At tlie top of barrel, immediately under the packing ring. Q. Why is it put there ? A. To let out steam when steam bound, and air when air bound. There should be a pet cock tapped in the cap of the valve cliamber to let off the steam or air when steam or air bound. Q. If you had no pet cock on the valve chamber cap, what would you do ? A. Simply take a wrench and loosen one of the nuts a little until the air or steam was out, then tighten it again. Q. Why is an air chamber put on a double action pump, and what is it? A. It is simply a copper vessel air tight. When the pump is working, the water is forced up into the chamber, compresses the air, and the air acts as a cushion on the valves and piston head in the water cylinder. — 34 — Q. Wliat is a cusliion ? A. A cushion is auythiiig that is com- pressed, and by its compression is formed into a higher and stronger pressure, consequently acting as a spring, deadening any knock that miglit- have occurred otherwise, as water will cause a knock, it being nearly as solid as iron, so if a double action pump had no air chamber, thei'e would be a continual thump- ing noise. Q. Wliat is a vacuum ? A. A vacuum is a space void of matter. Q. Can a perfect vacuum be formed ? A. No, about 9 to 11 per cent, of the atmos- phere, which is 14. V pounds per square inch. Q. Wliat will a vacuum do ? A. It will lift water 33 feet, providing all pipes and connections are air tight. Q. How^ is a vacuum created or made ? A. When the plunger of a pump is well packed and it lifts, it excludes the air out of the pump barrel i^nd suction pipe, conse- quently the water, being at the other end of the l)ipe, it follows the ])lunger; or, in other words, the atmosplieric ])ressure, being 14.7 pounds ])(_'!• scjuaix' iiicli, foi'ces the water up the ])ij)e to fill tlie vacancy made by the ]ilunger forming tlie vaenum. Q, What sliould be placed at llie bottom of the snction-})ipe ? A. A strainer made out of gauze wire, a foot valve and a pet cock to drain it. Q. If your pump sliould uot l>e workings your water running low, and you were asked to run a little while longer, would you ran and let your water become dangerously low ? A. Xo, take no chances whatever, but shut down and go about repairing the trouble. Q. AVliere would you look for the trouble ? A. Open the pet cock of the pump, and that will very neariy tell where to look for it; if no v^ater comes out, the water is shut off, or there is none, etc. Q. What generally prevents a pump from working ? A. Not enough water, too small a suction pipe and obstruction of the valves to seat, by straws, sticks or anything that may be drawn: through the suction pipe, or the pump valves becoming hot and sticking. — 36 — Q. If an accident happened, such as a "broken pipe connected with the boiler and purap, or you could not get sufficient water to supply the boiler, what would you do ? A. Simply shut down the engine and all valves connected with the boiler, draw fire, raise flue caps, and close the damper, so as to keep what water there is in the boiler until the difficulty is repaired. Q. If your suction pipe should spring a leak, vv^hat would you do ? A. Take a piece of sheet rubber, some cop- per wire, wrap around tight, and stop the leak temporarily. Q. If your hydrant, that sup- plies pump with water, should happen to get broken, what would you do ? A. First see how much water was in the boiler, by trjdng gauge-cocks, then shut off the water in the street, or wherever the lazy cock lay, and try to wrap it, if possible, or repair it. If an injector or inspirator was attached, and was supplied from a tank or well, use either. Q. For instance, if you had neither of these, what would you do ? — 37 — A. Shut down the engine, close the damper, raise the flue caps and draw the fire, wliichever suited the circumstances. Q. If your pump was turned around, could you feed the boiler? A. No. Q. What would be the consequence? A. If the ijackinof in the pump held out, the plunger would exclude the air and collapse the* discharge pipe. Q. Would it not have a tendency to draio the w^ater out of the boiler ? A. No, the check valve near tlie boiler would keep it back. Q. If you iiad no check valve, what would it do ? A. The water would run out, that is, pro viding the pump was turned, around. Q. If the pump plunger is one-half the Rtroke of the engine, what should the diameter of the plunger be ? A. One-third the diameter of engine cyl- inder. Q. Ilovr liigh should a valve lift to clear itself ? A. About one-foiirtli of its dhmR'tor or one- 111 i I'd of its area. Q. What proportions sliouki the valves be to any size J pumj) V A, They should be one-fourtli the ai'ea of the pump. Q. Suppose in the evening when you shut down, that the pump was in good woikijig ^order, and wdien you started up tlie next morn- ing and opened the pump pet cock a strong stream of water came out both strokes: where would you locate the trouble V A. The trouble Avould be at both the check and discharge valves being caught up, Q. Suppose you started the pump and it was in good order, and no water «ame; where would you locate the trouble ? A. The suction pipe is leaking, or it is out of water, or there is no ^vater. Q. State the usual area proportion of the cyl- inders of a steam pump ? A. The steam cylinder averages four times the area of the water cvliiider TPIE ENGINE. Q. What is a steam engiiu' ? A. A steam engine is a machine by which power is obtained from steam. Q. What is steam ? A. Steam is a gaseous vapor from water, generated by heat, composed of liydrogeii arid oxygen. Q. How do you know water is composed of hydrogen and oxygen ? A. Science shows that 1 pound of hydrogen wit]i 8 pounds of oxygen is equal to pounds of water. Q. What is an engine composed of ? A. A bed plate, cylinder, connecting rod, crank, crank-shaft, main pillow^ block, out pil- low block, crossdiead, wrist-pin in cross-head^ crank-pin, two cylinder heads, piston-rod, piston-head, follower head, bull-ring, packing- rings, follower plate and bolts, connecting rod and brasses, pillow-block brasses, a valve, and — 40 — guides where the cro88-head slides in, so the piston is kept central with the cylinder. The main pillow-block brasses are generally made into four pieces, called top, bottom and two quarter brasses four sides of shaft; they are made into four parts, so as to take up lost motion. Q. What keeps the rod from running off the crank pin ? A. The shoulder on the crank-pin. Q. Why are the stub ends of straps made heavier where the gib and key pass through? A. To make- up for the amount of iron taken out for the gib and key- way. Q. If water should accumulate in the cyl- inder, what would be the consequence ? A.* It is liable to crack the cylinder and dis- able the engine. Q. If you had (;harge of an engine in the country, and the cylinder head shonld ha])pen to crack, how would you remedy it '? A. If not broken too bad, try to j)atch it with pieces of iron oi" boards, and brace it from tlie wall Avitli a piece of lieavy scantling, then — 41 — try and run tlie engine until a new cylinder head could be made. Q. What size should a steam pipe and an exhaust pipe be to any size cylinder ? A. Tlie steam pipe should be one-fourth and the exhaust pipe one-third the diameter of the engine cylinder itself. Q. If your crank pin or other journals be- came hot, what would you do ? A. Try, while running, to get water on them, then oil them; if that would not do, j^top and slack up the key a little, then start up again. All engine cylinders should be well drained and heated before starting, then the engine should be started slowly, as the water that accumulates in the cylinder may injure the piston, cylinder, or cylinder heads. Always leave the cylinder cocks open when not run- ning, and they should remain so until the cyl- inder is heated by the steam, — after the engine has' been running at full speed two or three minutes at least. Q. If the cylinder had shoulders inside, and was out of a true circle, what would tou do to — 42 — remedy it ? A, Bore it, or liave it bored out. Q. In case the throttle valve should become loose from the stem and prevent the steam from entering the valve chest, what would you h faf>p pressure in fifiuring ii-i o\ver. Q. V/hatisI. H. P.? A. It is indicated horse power. Q. What is meant by cutting oil sleaiii at 6 inches? A. It means that tlie vaive closes and cuts; off the live steam from tlie boiler at 6 inches of the piston's travel : then tiie engiiie gets its power, from th.e tim-G tl^G valve closes or cuts off until the exhaust operis, by the expansion of the steam closed up in the cylinder. ^ Standard multiplers, Avith examples : 1. For the Area of a Circie. MulUpJy sq. of dip.m, by ,7So4 2 For Circumfereaceof a Circla, Multiply diHmeter bj b.l416 3. ForDiametar of ;i Circle, Multiply the cireuni. by .31831 •3. For the Surface of a Eali. Multiply sq of diam. by 3.3416 5. For the Cubic inches ia a Ball, Muitiply ». u^e of dia. by .5236 1. Rule for finding the area of any circle. Always multiply the diameter by itself, then by ,7854, then cut off 4 decimals to the right. 2. Rule for iiii = 254.4698. 5. KuLi-: to find the cubic inches in a ball. Multiply cube of the diameter by .5286; the answer e(}uals its solid contents. Example : Ball 8 inches in diameter; 3 x 8 == i)x3 = 27 X .5236 = 14^^jjV/,5- solid contents. Rule to iind pressure on the crown sheet of a hanging fire-dox boiler. Malli}>ly the width by the length in inches, then nuiitiply by steinn gauge pressu.re and devide by 2. EXAMPLE: Crown sheet 46 x 33 i]i. 46 Pressure 85 IV). 3<] Iron T in. 1518 85 If iron is i in. div. ]>y 4. 2.1129030 If iron is f in. div. ])y 2.66 2000;64515 lbs. press'e. 32. 2U tons '' liuLE to find how much water a boiler will contain. For 2-flue boiler, | full of water, find f of tlie ai'ea of the boiler in iiu-hes inside; mul- — TG — tiply by length in inches; then find area of flues, thickness of iron added; then nmltiply by 2, if two flues; multiply by length in inches, subtract area of flues from J contents, and divide by 231 (number of cubic inches in a standard gallon); the answer will be the number of U. S. gallons. p:xample : Boiler 48 inches. Two flues, 16 in. each 48 . 48 Lengtli 20 feet. 2304 16 .7854 16 3)1809.5616 area of Boiler. 256 .7854 603.1872 One-third of area. 2 201.0624 1206.3744 Two-thirds of area 240 .Length in inches. o 402.1248 28^529.8560 240 96509 .9520 Sub. Area of Flues. 96509.9520 231)193019.9040 835.5940 No. of Gallons. Rule to find the amount of water required, when the average pounds of coal used per hour is known. Divide the coal by 7.5; the answer will be cubic feet; then multiply by 7.5, and that gives tlie numberof U. S. standard gallons. EXAMPLE : 117 lbs. of coal used per lioiir, 7.5]117.0 15-6 7.5 117-0=117 gal.s. Q. How many cubic feet in 1 lb. of air? A. 13-/oVV cubic feet. Q. HoAV much air does it take to consume 1 pound of coal? A. It takes 18 pounds, or 248yV'(j^y cubic feet. , Q. How would you tell the amount of water any tank contained? A. If the tank was large at the bottom and narrow at the top, lay the tank off in 10 parts from top to bottom, then take the diameter -J=jj from the large end of the tank, square it, then multiply by .7854; that gives the area; then multiply quotient by full depth of tank and divide by 1728, which gives the number of cubic feet; multiply answer by 7.5, and the number of U. S. gallons will be given. The example must be done in inches; 1728 is the number of inches in a cubic foot, and 7.5 is the number of gallons in a cubic foot. EXAMPLE: Tank 2 feet diam. 24 inches diameter. Tanks feet deep, 24 '' 576 .7854 452.3904 area in inches^ 36 inches deep; 1728)16286.0544 9.4248 cubic feet. 7.5 No. gals, in a cub. ft. T0.861W0 U. S. gah. in tank. Rule how to mark eugineer's tools. Warm the tool and allow a thin coat of beeswax to cover the place to be marked; after the bees- wax is cold, take a dull scriber and do the marking; then apply some nitric acid, after a few moments wash off the acid with water, then heat the tool to melt the beeswax, and you will find well defined marks. Rule for chimneys. Chimneys should be round inside, instead of square, to insure a good draft. The opening should be one-fifth larger than the area of the fines or tubes com- bined; if less, the draft will not be free. The opening from tlio bottom sliould increase in — I'iJ — size to the top, and be smooth iuside. Rule for making good babbitt metal, for high and low speed, in parts. HIGH SPEED. ; COMMON. MEDItJM. Martin's Nickel : 10; Copper. 13 4 84 100 Copper Antimony Tin m Copper 1 16 Antimony 1 4 Tin 1 70 Antimony Tin 25 liool 100 Rule for babbitting a box. Nearly every engineer has his own way; but the best and quickest way is to chip out ail the old babbitt in the cap and box, then put the journal or shaft that is to run in the box in its j)lace; put enough liners in between the shaft or journal and edge of box until level, square and in line; put thick putty around the shaft and against the box, so the babbitt can not run out; then heat the babbitt until it runs free, and pour accordingly; the cap is then bolted in its place upon -^j inch thick liner, and putty placed as before; then pour metal through the oil holes, which will have to be drilled out after- wards. — so — Rule to determine the capacity of any size pump, single or double action. Multiply the area of the water piston-head face or plunger in inches, by its stroke in inches, which gives the number of cubic inches per single stroke; the answer divided by 231 (the cubic inches in a gallon) will give the number of standard gal- lons pel* single stroke. But remember, all pumps throw less water than their capacity^^ which depends upon the condition and quality of the pump. This loss arises from the rise and fall of the valves; from a bad fit or leak- age, and in some cases from there being too much space between the valves, piston or plun- ger. The higher the valves have to rise to give the proper opening, the less work the ])nmp will perform. Q. Will a boiler 60 inches in diameter, f inch iron, stand as much pressure as a boiler 48 inch diameter, f inch iron? A. No. Q. Why? A. Because the pressure in the large boiler has more surface, and will not allow it. It is the same as a long bar and a short bar of the — 81 — same thickness; it takes less strain to break tlie long one than the short one. RrLE for finding safe working pressure of steam boilers. Always use .56 for single riv- eted and .TO for double riveted side seams. A radius means A- the diameter and 4- of ten- sile strenofth is safe load. U. S. standard is f. Multiply the thickness of iron by single or double rivets, then multiply by the safe load, divide by internal radius, and the answer will be the safe working pressure. EXAMPLE: Diam. 42 in. .1875 thickness of iron. Iron v^s in. .70 double riveted. Double riveted .131250 -50,000 lbs. tensile str'th. 10000 2)42 20.8125)13125000.00 21 ^^^^ Safe working pressure, 63.06 .1875 5 20.8125 i-|iJt Bursting pressure, 315.30 Rule to find aggregate strain caused by the pressure of steam on the shells of boilers. Multiply the circumference in inches by the length in inches; multiply this answer by the — 82 — pressure in pounds. The result will be the pressure on the shell of boiler, and divide bj 2000, which gives the tons. EXAMPLE; Diam. of boiler 48 inches, circumference 150.7968, length 20 feet, or 240 inches, pressure of steam 120 lbs. 150.7968 X 240 x 120 = 4842947.8400 lbs., divided by 2000 = 217U tons strain. Rule to find the number of feet of 1 inch pipe required to heat any size room with steam*. For direct radiation 1 lineal foot (straight foot) to 25 cubic feet of space. For indirect radia- tion, 1 lineal foot to 15 cubic feet of space. Note, all pipe is measured inside for size. EXAMPLE: Room 18 X 18 X 18 to be heated with 1 inch, pipe. Direct radiation. All calculating must be done in inches, and divided by 1728 to find the cubic feet. 216 216 46656 216 172 8) 100 77696 cubic inches. 25)5882 cubic feet. Lineal 233/2^ feet of 1 inch pipe. One cubic foot of boiler is required for every 1500 cubic feet of space to be warmed. One horse power of boiler is enough for 40,000 cubic feet of space. Rule to find the horse power of a boiler. Always find the number of square inches and divide by 144, which givtjs the square feet of heating surface, and divide by 15 square feet, wbcih is an average allowance for one horse power of a boiler: divide the II. P. by 2, you will have the proper grate surface, and allcvr J square inch of safety valve to each square foot of grate surface. Generally, from ^ to f of a square foot of grate surface is allowed to each horse power of a boiler. Q. How do you find the horse power of a boiler? A. Find the number of square feet of heat- ing surface and divide by 15; 15 square feet of heating surface is the general allowance for a H. P. of a boiler. (See following example.) — 84 — EXAMPLE: Boiler 48 in. x 25 ft. First find circum. of boiler. Two 1(3 in. flues. 16 i"- diam. of 1 flue. 48 diam. of shell. 3.1416 3J416 50.2656 circ. of 1 flue. 3)150.7968 300 length of flue. 50.2656one-third circum. 15079.6800 in inches. 100.5312 two-thirds " 80159.3600 heat. sur. 2 fl. 300 length or boiler in inches . 30169.3600 No. sq. in. heat. surf. 16 in diam. of 1 flue, in the shell. 16 48 ^56 48 .7851 f>3()4 201.0624 area 1 flue. .7854 . 2 3)1809.5616 area of 1 head. 402. J 248 area 2 flues, 603.1872 one-third area of 1 hcL 2 2 804.2496 both ends. 1206.3744 two-thirds area of 1 hd. 2 2412 7488 two- thirds area of both heads. ^o:^. in. heat. surf, m sheU, 80159.8600 Two-thirds area both heads, 2412.7488 Total, ^"3f3 Subtract area of flues, S0^.2m Thisboileris28h.p. An 144)61927.2192 engine nses about i of boil- 15( 480. sq. f t . h. s . er's h. p.. making this boil- 2(28^ h. p. er sufficiently large enough 2(14, grate surf. to supply engine of 56 h. p. 7. area s'fty v. — 85 — Number sq. feet of heating siivfiice allowed for tubular boilers are 12 sq. feet. Plue boilen^ 1.S sq.. feet. Cylinder boilers 7 sq. feet. Rule to find the horse power generated iu any kind of boiler when running. First, notice how long it will take to evaporate 1 inch of water in the glass gauge, divide this into 60, which gives the number of inches evaporated in one hour; second, multiply the aA^erage di- ameter where evaporation took place by the length of the boiler in inches; tliis multiplied by the number of inches evaporated, and the answer divided by 1*728 gives the cubic feet ol" water evaporated in one hour. As a rule, 1 cubic foot of water evaporated ifir generally allowed for 1 horse power; also the capacity of a pump or injector for any boiler should deliver 1 cubic foot of water each horse power per hour, and an engine uses one-third of a cubic foot of water j^er horse power. EXxlMPLE: Length of boiler 216 inches. 216 Average diam. 40 inches. 40 One inch evaporated in 15(60 8640 15 minutes. 4 4 1728)84560(20 h. p. Weight of Square Superficial Foot of Boiler Plate w heist Thtckis^ess is Known. Thickness. Weight.! lbs. ; 1.25 ! Thickness. Weight. Incheti. Dec. Inches. I)ec. lbs. tV = -^-^^^ J'r = -3125 12.58 ^V == -0025 2.519 ' : 1 = .375 15.10 ^3_ = .0987 8.788 ' i\= -4375. 17.65 1 =. .125 5.054 i = .0 20.20 3^ =: .1562 G.305 1- rr .625 22.76 tV = -l'^*^^ 7.578 25.16 WV = .2187 8.19 1 = .75 30.20 i -= .25 10.09 , A :.. .875 85.30 ^ = .2812 11.88 I = .1 40.40 Q. Explain how the above fractional j^arts of whole numbers are made to read as decimals — take yV of an inch for an example? A. To do this take 100 as a whole number; divide 16 into 100 ^ 6^-, reads .625 == ^\ of 100. ould read X .625 = .1875. Tliis principle answers for all the rest. Rule for safety valves. To find tlie distance ball should be placed on lever, when the weight is known, or the distance is known and weight is not known. Multiply the pressure required by area of valve, multiply the answer by the fulcrum; substract the weight of the lever^ valve and f^tuui, aiul div'ulc l)y tin- v.eight of ball for distance, or divide by distance for weight of ball with tlio same example as fol- L'WS: EXAM PL i-:: Weight ol' ball, GO lbs. 100 ibs. pressiue. Fret>«ure, 100 " _ 3 area of valve. Wt. of 1. . y . & steam. 80 • ' 300 Fulcrimi, -1 i^^^'^b__ -i fulcrum. Area of valve. ;> "' T200 30 wt. of L. y. & St. 60)1170 19i inch ball should be hung" on lever. The mean effective weight of valve, lever and stem is found by connecting the lever at fulcrum, tie the valve-stem to lever with a string, attach a spring scale to lever immedi. ately over valve, and raise until the valve is clear of its seat, which will give the mean effec- tive weight of lever, valve and stem. Rule for figuring the safety valve and to know the pressure when the area of valve, the weight of lever, valve and stem, the distance fulcrum is from valve, and weight of ball is known. Divide fulcrum into length of lever, multiply — 88 — answer by weight of ball, add weight of lever, valve and stem, and divide by area of valve. Answer will be steam pressure. Weight of ball, 50 lbs. 2.2-5 4)20 Wt.ofL.y. and stem, 30 lbs. 2.2.5 5 Fnlcnmi, 4 in. 5.062-5 oO Biam. of valve, 2i in. .7854 250 Length of lever, 20 in. 8.97608750 area. 30 Add as many ciphers to the divi- 3.9)280.0 dend as there are decimels in the di- Ibs.press. 71. |i visor, and divide as whole numbers. To measure or mark off the lever, you measure the fulcrum and make notches the same distance as fulcrum; if fulcrum is 4 inches, each notch must be 4 inches apart. Q. What is meant by a fulcrum? A. The distance valve stem is from where the lever is connected. Rules for Machinists. RuLK TO Gear a Lathe for Screw-Cut- ting. — Every screw cutting lathe contains a long screw called the lead screw, which feeds the carriage of the lathe while cutting screws; upon the end of this screw is placed a gear to which is transmitted motion from another gear placed on the end of the spindle; thes^e gears each contain a different number of teeth, for the purpose of cutting different threads, and the threads are cut a certain number to the inch, varying from one to fifty. Therefore, to find the proper gears to cut a certain number of threads to the inch, you will first multiply the number of threads you desire to cut to the inch by any small number, 4 for instance, and this will give you the proper gear to put on the lead screw. Then Avith the same number, 4, multi- ply the number of threads to the inch in the lead screw, and this will give you the proper — sa — — 90 — gear to put on tbe spindle. For example, if you want to cut 12 to the incb, multiply 12 by 4, and it will give you 48. Put this gear on the lead screw, then with the same number 4, multiply the number of threads to the inch in the lead screw. If it is 5, for instance, it will give you 20; put this on the spindle and your lathe is geared. If the lead screw is 4, 5, G, T or 8, the same rule holds good. Always multiply the number of tlireads to be cut first. Some — indeed, most small lathes — are now made with a stud geared into the spindle, which stud only runs half as fast as the spindle, and in finding the gears for these lathes you will first multiply the number of threads to be cut, as before, and then multiply the number of threads on the lead screw as double the number it is. For instance, if you want to cut 10 to the incii, multiply by 4, and you get 40; put this on the lead screw, then, if your lead screw is 5 to the inch, you call it 10, and multiply by 4, and it will give you 40. Put this on your stud and your lathe is geared, ready for cutting. Rule for Cutting a Scuew ix an Engine — I — Lathe. — In ciittiiig V-thread screws, it is only liecessavy for you to practice operating the shipper and slide screw-liandie of j^our latho before cutting. After liaving done this iintir you get tlie motions, you may set the point of the tool as high as the center, and if you keep the tool sharp you will iind no difficulty in cut- ting screws. You must, however, cut very light chips, mers scrapings in finishing, and must take it out of the lathe often, and look at it from both sides very carefully, to see that tlie threads do not lean like fish scales. After cut- ting, polish witli a stick and some emery and oil. Rule for Cltttixg Square Thread Screws. — In cutting square thread screws, it is always necessary to get the depth required with a tool somewhat thinner than one-half the pitch of the tiiread, after doing this make another tool exactly the })itch of the thread and use it to finish with cutting a slight chip on each side of the groove. After doing this, jwlish with a pine stick and some emery. Square threads for strength should be cut one-half the deptli of their pitch, while square threads for wear may — and should be — cut three-fourtlis the depth of their pitch. Rule for Mongrel Threads. — Mongrel, or half Y half square threads, are usually made for great wear, and should be cut the depth of their pitch, and for extraordinary wear they may be cut 1^ the depth of the pitch. The point and the bottom of the grooves should be in width J the depth of their pitch. What i» meant here by the point of the thread is tlie outside surface, and the bottom of the groove is the groove between the threads. In cutting, these threads, it is proper to use a tool the shape of the thread, and in thickness about ^ less than the thread is when finished. As it is impossible to cut the whole surface, at once, you will cut it in depth about j\ at a time then a chip off the sides of the thread, and continue in this way alternately till you have arrived at the depth required. Make a gauge of the size required between the threads and finish by scraping with water. It is usually best to leave such screws as these a little large until after they are cut, and then turn oft alight — 93 — chip, to size them; this leaves them true an* nJcc. Rule to Temper Tools Used Daily, Suck AS Chisels, Taps, Dies, Rsa^meks, Twist Drills, Common Flat Drills, and Latiib Tools. — To temper flat, cape or side chisels, and common fiat drills, put the tool to be tem- pered in the fire and heat slowly to a cherry red <;olor, about 4 inches from the point. Then take it out and put it in the water, point first, about three or four inches, then draw it back n of the cut off cams, which are moved and controlled by the governor. ' Q. Does the cut-off cams trip the hook al- ways at the same point? A No. The cut-off' is determined by the requirements of the load on the engine. Q. By what name is this cut-off known? A. The automatic cut-off. Q. How is the theory of the Corliss va?'*^ motion easily understood? — 09 — A. The theory is easily understood by con- sidering tlie four valves as tlie four parts (or edges) ()( a common slide valve. Q. Why are the four valves of the Corliss engine considered as the four parts (or edges) of the common slide valve? A. The working edges of the two steam valves answering as the two steam edges of the slide valve, and the working edges of the two exhaust valves as tlie exhaust edges of the slide valve. Q. The Corliss having four valves, and the common slide valve only one, does it not make any difference in setting? A. As far as the setting the principle is the same; the only difference is in the adjustment. Q. Why does the adjustment make a differ- ence? A. The four working edges of the common slide valve are in one solid valve, so that any change or adjustment of one of the edges inter- feres with the other three. If one edge is to be changed in reference to the others, it must be 4one by altering the valve itself. The Corliss — 100 — valves, on the other hand, are adjustable, each by itself, and any one of the valves may be changed without disturbing the other three. Q. Can the adjustment be made while run- ning '? A. When the engineer is familiar with his engine and knows what changes are necessary, the adjustment may be, and is frequently, made without stopping the engine. Q. ITow many edges has a slide valve ? A. Four — two steam and two exhaust , Q. Has the Corliss valves the same number of edges as the common slide valves? A. No. Each Corliss valve represents an edge of the common slide valve, viz.: two steam edges, two steam valves, two exhaust edges, two exhaust valves. Q. IIow are the valves connected to the ec- centric and worked on Corliss engines? A. With the wrist-plate, carrier arm, rocker arm and reach rod. Q. Is the wrist-plate good for any other pur- pose? A. Yes. It niodiiies the speed of travel at — 101 — different parts of the stroke, in relatiuii to each other, and gives a quick atid constantly increas- ing speed wlien opening tlie steam valves, and a quick opening and closing of the exhaust valves. Q, When do the steam and exhaust valves travel slowest? A. When they are closed. Q. Can the valves of Corliss engines be adjusted when the reach rod is unhooked from the wrist-plate, so the valves maj he properly set, independent of the position of the crank? A. Yes. Q. Are the Corliss valves easily set? A. If the engineer has any knowledge, as he should have, of the ordinary slide valve, and of the effect of "lap and lead" as applied to its. working, and will consider the Corliss valve gear in the light of this knowledge, he will soon master the seeming difficulties in his way and find the Corliss gear to be the simplest, most perfect and most easily adjusted of all valve motions. Q. How would you go about setting the Corliss valves? — 102 — A. Begin by taking off the back caps or back heads of all four valve chambers. Guide lines will be found on the ends of the valves and on the ends of the chambers, as follows: On the steam valves, coinciding with the working edges of the valves; on the steam valve chambers, co- inciding with the working edges of the steam ports. On the exhaust valves and ports, guide lines are also scribed to set them by. The wrist- plate is centrally between the four valve cham- bers, on the valve gear side of the cylinder. A well defined line v>'il] be found on the stand which is bolted to the cylinder, and three lines on the hub of the wrist-plate, which, when they coincide with the line on the stand, show the central position of the wrist-plate and the ex- tremes of its throw or travel. To adjust the valves, first unhook the reach rod connecting wrist-plate with rocker arm and place and hold the wrist-plate in its central position. The con- necting rods between steam and exhaust valve arras and wri>t-plate are made with right and left hand screw threads on their opposite ends, and provided with jamb nuts, so that 1 y slack- — los- ing the jamli, nuts and turning the rod they can be lengthen'^d or sliortened as desired. By means of this adjustment, set tlie steam valves so that they will have ^ inch lap for 10 inch diameter of cylinder, and 4- inch lap for 32 inch diameter of cylinder, and for intermediate diam- eters in proportion. For the exhaust, set them with 1-16 inch laj) for 10 inch bore, and -^ inch lap for 32 inch bore on non-condensing engines and nearly double this amount on condensing engines, for good results. Lap on the steam and exhaust valves W' ill be showai by the lines on the valves being nearer the center of the cylinder than the lines on the valve chambers. Having made this adjustment of the A^alves, the rods connecting the steam valve arms with the dash pots should be adjusted by turning the wrist plate to its ex- tremes of travel and adjusting the rod so that wdien it is down as far as it will go, the sq. steel block on the valve arm wall just clear the shoulder on the hook. If the rod is left too long, the steam valve stem w^ill be likely to be "ither bent or broken; if too short, the hook will — 104 — not engage, and consequently the valve will not open. Having adjusted the valves as stated, hook the engine in and, with the eccentric loose on the shaft, turn it over and adjust the eccen- tric rod so that the wrist-plate will have the correct extremes of travel, as indicated by the lines on back of hub of wrist-plate. Then place the crank on either dead center and turn the eccentric in the direction in which the engine is to run to show an opening at the steam valve of from 1-32 to ^ inch, depending upon the speed the engine is to run. This opening will be shown by the line on the valve being nearer the end of the cylinder than the line on the valve chamber. This opening gives the "lead" or port opening when the engine is on the dead center. The faster the engine is to run the more lead it requires, as a general rule. Having turned the eccentric so as to secure the desired amount of lead, tighten it securely, by means of the set screw, and turn the engine over to the other center, and note if the other steam valve has the same lead. If not. adjust by length- ening or shortening the connecting rod to the — iOJ — wrist-plate as the case may be necessary to do. If the engine has the lialf-moon, crab claw, or other gear which opens the valves toward the center of the cylinder, the manner of the adjust- ment will be the same, except that the "lap" on the steam valves will be shown when the line on the steam valve is nearer the end of the cyl- inder, and the 'dead" when this line is nearer the center of the cylinder than the line on the valve chamber. The adjustment of the exhaust valves and the amount of "lap" and "lead" will be the same in either case. To adjust the rods connecting the cut-off or tripping cams with the governor, have the gov- ernor at rest and the wrist-plate at one extreme of its travel. Then adjust the rod connecting with the cut-off cam on opposite steam valve so that the cam will clear the steel on the tail of the hook about 3^^ inch. Turn the w^rist-plate to the opposite extreme of travel and adjust the cam for the other valve in the same manner. To equalize the cut-off and test its correctness, hook the engine in and block the governor up about 1^ inch, which will bring it to its average — 10(3 — position when running. Tlicn turn the engine slowly, in the direction in which it is to run, and note the distance the cross-head has traveled from its extreme position at dead center when the cut-off cam trips or detaches the steam valve. Continue to turn the engine beyond the other dead center and note the distance of cross-head from its extreme of travel when the A^alve drops. If the distance is the same as when the other valve dropped the cut-off is equal. If not, adjust either one or the other of the rods until the dis- tances are the same. By following these directions, the engine will do good work, but to know just what it is doing the engineer shoukl use the indicator often. Ko engine room is complete without a good indi- cator, and no engineei' can be well posted as to what his engine is doing and keep it in its best possible condition for good work without hav- ing an indicator and using it often. (See p. 68.) THE DYNAMO. Q. What is a Dynamo V A. A Dynamo is a machine in which Elec- tricity is gathered and forced out through wires for lighting, Electro-plating, etc. Q. What does a Dynamo consist of? A. A Dynamo consists of a field, frame, arm- ature, commutator, brushes, brush holders, pins for the brush holders and a quadrant. Q. What is meant by a held ? A. It means the magnets connected to the frame with bolts. Q. What are magnets? A. Magnets are iron cores, wound with insu- lated wire. These magnets are called electro- magnets because they become magL^tic only when a current passes through the wire. Q. How is the current generated? A. By the rotary motion of the a /mature between the poles of the magnet. Q. What does an armature consist of ? - lOT — — 108 — A. It consists of either a steel or iron shaft, around which insulated wire is wound, the shaft liaving a 6 or 8 inch bearing at each end. Q. How is the current conducted to the lamps? A. By means of brushes m^de out of copper strips or wires about 6 or 8 inches long, sol- dered together at one end and held on the com- mutator by means of brush holders made out of brass. These holders are on long pins, the pins are nutted to a quadrant and the quadrant is fastened to the frame. Q. How many brushes are there generally, and where are they? A. There are 2 and 4 brushes, two on one side of the commutator and two directly oppo- site, according to size of machine. Q. What is a commutator? A. A commutator is made out of segments of copper and segments of insulation. Q. Can a commutator be taken off when worn out? A. Yes. Q. How is it generally done? A. By taking out the brushes, brush hold- —109 — ers, the pins and the armature from the dynamo, then pla?e the two ends of tlie shaft on wooden horses, mark the wires connecting the armature and commutator by attaching numbered tags (so i.,8 to place them, when the new commutator is put on) then disconnect the wires between the commutator and armature and take off the com- mutator from the shaft. Q. How should a dynamo be looked after and run ? A. See that the machine is clean, Journals cool, and that the proper speed is kept up; see that the brushes are directly opposite each other and that the quadrant and brushes are moved around on the commutatar according to tlie number of lights in use. Q. How would you know when to move the quadrant? A. By the sparking of the brushes on the commutator. Q. What mainly causes the dynamo to flash or spark ? A. The brushes not being directly opposite through the diameter of the commutator, some- — 110 — times not enougli pressure on the commutator, sometimes the brushes not far enough around on tile commutator, also too much brush surface. Sparhling at the brushes. Some styles of dynamos will spark at the brushes in spite of anything the attendant can do to prevent it, but many other styles of dynamos can be run with absolutely no sparks on the commutator. The first point to be attended to is to get your com- ^nutator perfectly smooth, or as near it as 2->ossi- ble, with the means at your command, for if the commutator is not true you can not prevent it from sparking. If you have a slide-rest, use it, and get your commutator round and true from end to end. If you have no slide-rest, a 16 in. bastard file will do nearly as well. Take the brushes and brush holders off, so that you may have plenty of room to work. Start the d^'namo to turning very slowly. Hold a piece of chalk so near the commutator that it will mark all of the high spots. Move the chalk slowly from end to end of the commutator, so that all high places on the full length v^dll be chalked. Stop the — 1 i :i — clynaiuo aii«l amusi' j'oui'self liliiig off tliose parts tliat have been marked by tlie eliulk. If you have noticed wliile the dynamo was turning about how much the eoramutator was "out," you can easily tell about how much you will have to file away to bring it true. File off all the places that have been marked, and then start up again slowly, and chalk it again. Repeat the chalking and filing until the commutator is round, and of the same size from end to end. Next get a piece of shingle, thin board, or a piece of lathe even will do, and wrap a sheet of No. oo. sand-2Japer around it — never use emery })aper or cloth — start the dynamo at a pretty lively speed, and smooth the commuta- tor down with the sand-paper, holding the flat side against the work. It is not necessary to work it down to ?i poUsJied surface, although it would be well if it were polished. Now that you have your comm.utator round and smooth — and it must be so smooth that there are none of the marks left on the commutator, for it was trouble that caused them, and if any be left they will certainly cause more trouble. — 112 — Now, that yon know your commutator is in good shape, proceed to set your brushes, being certain that the points of opposite brushes are directly opposite through the diameter. The pressure put on the brushes need only be just sufficient to make good contact. It is not neces- sary to have much pressure to preserve good contact. Should the contact be too slight it will make itself known by a j^eculiar noise that is indescribable, being neither a snap, crack or pop, and yet might be called by either of these names. You may be sure that the noise will call your attention if you are anywhere near, and after you have once noticed it you will easily recognize it the next time. This noise and considerable sparking will always be present when the brushes do not press heavily enough upon the commutator. If the brushes are not set with the points directly opposite, sparking will result. If the brushes are set ahead of the neutral line or back of it they will spark. When setting four brushes on a commutator that requires two brushes side by side, it is — 113 — >ometimes difficult to get all four of them (»f an equal length, or evenly divided on the coiu- mutator, one or more of them will spark more or less. After rocking the brushes back and forth a. trifle to find the point of least sparking, you can then tell by the color of the spark wliether the brush should be lengthened or shortened. When the spark is of a decidedly greenisli color the brush is too short, but if the sj^ark appears to spatter and shows a reddish line, then you will find that the brush is too long, or it is so worn that there is too much of it in contact. By the way, you will find fully .as much, if not more, trouble arising from having too much of the brush in contact, than from liaving too little. Oil' ting of Commutatoi'y scratching and eat- ing away of the segments, is mostly due to the Ibrushes having too much surface in conta^Jt, and increase of ])ressure Avill wear away the com- mutator, and having loo much of the face of the brush in contact will cause an edge of the segments to become eaten away, and if not at- tended to, they will, in a very short time, bo- — 114 — come as rongh nn«] uneven :v^ a corduroy road. With the thicker style of biushes we havt'^ Bever found it necessary, even wluen running at full load, to have more than one-third of the full end surface of the brush in contact witli ihe commutator, and further, we have found tliat if we allowed the brush to become so worn that even one-half of the end surface bore on the segments it would cause sparking. To prevent filing the l>rn,shcs every day (which would be wasteful), to keep them in the bt3St of order, we found that they could, with great atvantage, be turned the otlier side •p and allowed to wear in tliat way until the eurf ace became to great. This resulted in get- ting more than twice the amount of work out of a brush than was possible by filing always from one side, or trimming the ends squaie as often as they became badly worn. If the com- mutator becomes very hot you will b»>^fii^t^ Bure to find that your brushes are badly wotii. ■ I^lat iipots on tlie commutator, frequently ex- plained by laying it to soft spots in the coppei', we have always found to res^ult from an entirely different cause. When the marks hiwv tlie ap- jjearance of a blow from the pene of a liammer^ it will generally be found to be caused by a loosely connected or badly soldered armature wire connection. A spot of this kind contin- ues to grow larger until the cause of it is removed and the commutator dressed dowir i-mooth. At the end of the segments a spark or stream- of tire encircling the whole como-^ntator will Horaetimes be noticed. This nuif/ be caused by an accumulation of' oil or copper-dust or dirt, that causes a shorf circuit, but it will generally be found that the' insulation is charred or burned through at some' place near where the spark is noticed, and if iv careful examination of the armature wires ai(? made you will find that a connection is loose or }ia8 very poor conductivity. Allowijigthe eoiii-' mutator to run h&t will increase difficulties of' ihh kind. : Tlie Pfiociple of tli8 rijiiasio m^mi wit-li (lie Sleaiii Fyiiiji \\e are often asked Low can a dynamo be L>a,si]y understood; the questions coming from engineers Avho have charge of electric lighting |--!aiiLS. The whole thing may be compared, in its ];ri])c!|)les, to the working of a steam pump forcing water through aline of pipe of the same extent as the line wires. The dynamo (or pump) foices electricity instead of water. So long as the dynamo or pump works continuously the pipes or wires are filled witii a current of water, or electricity, flowing in one direction; in other word.s^a continuous current. Thus we maysaj: that a certain number of pounds steam pressure is required to overcome the friction of the water in the pipes, so that so many cubic feet or gal- lons of water shall be delivered ].cr minute, equally true we can say, so many volts are r.^- — litj — — 1 17 — quired to overcome the resistance of tlic wire, so tliat the current shall be delivered in so many amperes per minute. Hence, to simplify, we may say pounds of steam pressure = volts; the friction==resistance; the pipe==the wire; current =volume of water in motion, and amperes of electricity==gallons of water delivered at the ^nd per minute. Every engineer knows that tlie larger the pipe the more gallons water per minute, and the less relative friction, so tlie larger the wire the more current can be carried and the less the resistance, relative to the num- ber amperes delivered. The same analogy liolds- good in the opposite, for the smaller tlie pipe or wdre, the greater tlie friction, or resistance.. Every engineer who uses a steam pump or ant injector, knows that there is some poirit to» which, if his pipes were reduced in size, neaily or quite all his power ^^(steani pressi^^rej would be absorbed in friction. So electrically, our voltage may be largely consumed or absorbed by too small a wire; in either case — eitlier the water or the electricity — the result of tlie work done J8 in both cases uniform and identical, viz.; A — 118 — contiriiious current, and is tbe current that lias been generally used fov the production of light and power. The other current, which is largely employed in the generation of electrical power viz.: the alternating current, differs essentially from that which we have described above, and infact our analogy to the working of a pj^inip comes to an end. The current from an alter- nating dynamo, instead of flowing continuously and directly, is simply a vibratory movement, or a "back and forth flow.'' Here the suprenj. acy of electricity as a power, or rather as a transmitter of power, comes in, for, returning to cue pump, should we at each alternate stroke of the pump reverse the direction of flow of the water, the entire power, or nearly all of it, would be absorbed by its weight, and the fric- tion in the pipes. But electricity boing without weight, there is of course no loss by reversing its flow; indeed, the possibilities of aj^plicaMon to useful service, dependent on the reversals, are of the greatest value. To clearly explain the action of the alternating system, we have to t'onsi.lcr the requirements under which elec- — 110 — tricitv does its most acceptable y/ork. Every engineer wlio is iriiiking electric lights knows that the most satisfactory results, L e., the best light, is obtained by using a dynamo and distributing system oC as high voltage aa possible, in conjunction Avith a lamp of low Toltage. Here, then, we have tM'o actually op- posite conditions, which must be harmonized to produce a perfect I'esult in their action, and which are plainly impossible in the continuous current system, which we have explained by the comparison to our pnmp; because it is evi- dent, to renew the comparison; that if we are carrying a pressure (steam), and our line of pipes is calculated to deliver a certain amount of water per minute, if we throttle down at the delivery end, so as to deliver only -^'^ or „\ of the amount, we shall only be able to do so by reducing our pressure relatively, involving a .gre.{3it. loss of efficiency, or incur tlie risk of destruction to the plant at some point. Hence we are obliged to provide some appli- ance which shall intervene to convert the high voltag-e of the dvnamo and circuit to the low — 120 — -voltage of the lamps. When such an appliance?- is used it is known as a converter sj^stem, and the use of an alternating current and converter system are mutually dependent on and necessary to each otlier. This system can be compared to the en- gineer's system of steam heating in his build- ing thus: Suppose he carries 75 lbs. boiler pressure, and tlie steam is carried into the build- ing in one main pipe, and from that is dis- tributed by risers, etc., to the different radiators in the building. It is evident that he has no use for full boiler pressure on the risers and radiators, as, even if they would stand it for a time, it would be no more effective for heating than a reduced pressure; hence he puts iii a reducing valve in the steam main, between the boilers and risers. So, then, the converter used in connection with an alternating current is exactly an elec- trical reducing valve, with a high pressure (vol- tage) on one side, and a low working pressuie (voltage) on the other. Thus, by using this oonverter he may carry any voltage at the — 121 — dynamo and primary circuit, reducing into the secondary, to conform to the amount of current required. Each current continuous or alternate, have especial fields to which they are adapted, and while both are extensively in use each has its peculiar adaptation. Q. How do you understand the term "volt?" A. The "volt" is a measure of electro — motive force, or original energy. Corresponding- to the dynamic term "pressure," but not of "power." It is based on the product of one Daniell cell of a battery. Q. How do you understand the term "ohm?" A. The "ohm'* is the measure of resistance, and compares to the dynamic term of "loss by transmission." It is based on the resistence offered by a copper wire .05 in. diameter, 250 ft. long; or a copper wire, 32 gauge, 10 ft. long, Q. How do you understand the term "ampere?" A. The" ampere," is the measure for current or what passes; the intensity, it may be called, and is comparable to the dynamic term of "power transmitted," or "effect." It is the res- — 122 — idual force of one "volt" after passing tliroiigli one "ohm" of resistance. Q. How do you understand the term "cou- lomb?" A. The "coulomb" is a measure of current, qualified by time; one ampere acting for one second of time, comparing in nature with the dynamic "foot-pound." Q. How do you understand the term "watt?" A. The "watt" is the unit for dynamic effect produced by electro-motive force or current. It equals 44.22 foot-pounds, or one 746 h. p. Q How many "coulombs" in a "watt?" A. There are 44.22 "coulombs." Q. How many "watts" in an electrical h.p.? A. There are 740 "watts" in a li. p. Q. How many horse power will it take to run a 50 arc light dynamo. Each arc light equaling 45 "volts" and 8 "amperes" giving 1600 candle power to each light? A. Multiply the "voltage" by the "amperes" then the number of lights lit, and divide by electrical h. p. which is 146 "watts." The an- swer will be the h. j>. of engine re([uired. Recsists for Sold ?M Mm Platiog. Take a tablespoonful Cyanide of Gold and |)Ut it in a gla^s of water, to do gold plating. All articles to be plated should be dipped in strong lye or diluted nitric acid, and rinsed off with soft water; then place the article to be plated in the glass that has tlie solution of either gold or silver, and take a couple of pieces of zinc 1 inch wide, and double to ^ in. wide, by 10 long, let it touch the article to be ])lated, atid you will be surprised at the result. This answers for both. To make solution of silver for plating: — Take silver and dissolve in a glass witli little nitric acid, when the silver is dissolved then drop- by- droloric acid in until the white precipitates, (silver chloride) ceases to fall, pour off the col- ored water after it has settled, and add soft water to it, then it is ready for use. POINTS FOR EEINEERS. Steam-Pipes, wheUier for power or for heat- ing, slioiild always pitch downward from the boiler, that tlie condensed water, etc., may have the same direction as the steam, or other- wise there will be trouhk', unless the pipes are either very short or very ]arge. Globe valves should always be so placed in steam-pipes that their stems are very nearly horizontal, in order to prevent a heavy accumu- lation of condensed water in the pipes. Where- e.ver a horizontal steam-pipe is reduced in size there sliould be a drip to avoid filling the larger pipe partially with condensed water. In order to make a rust joint that will stand heat and cold as well as rough usage, mix ten (10) parts of iron filings and three (3) parts of chloride Of lime v/ith enough water to make a paste. Put the mixture on the joint and bolt firmly; in twelve hours it will be set so that the iron will break sooner than the cement. — 124 — Rules for Caicolaliiig Speed and Sizes of Pulleys. To HikI tlie size of driving pulley. Multiply the diameter of the driven by the number of revolutions it shall make, and divide tlie answer by the revolutions of the driver per minute. The answer will be the diameter of the driver. To find the diameter of the driven that shall make a given number of revolutions: Multiply the diameter of the driver by its number of revolutions, and divide the answer by the number of revolutions of the driven. The answer Avill be the diameter of tlie driven. To find the number of revolutions of the driven pulley: Multiply the diameter of the driver by its number of revolutions, and divide by the diam- eter of the driven. Tlie answer w^ill be the number of i-evolutioiis or the driseu. TaDI.K Ofc' DlAMETKlxS AM> ClU CM'MFKKENCF.IS OK ClRCLKP. TABry^: SnoAVrNd thk Aukas OK'I'lSi: DlAM^yj'KRS OF CIR- CLES A N 1> A H K AS OF Cl V.Cl.V.ii Bia. Cir. Dlam. .:J9-.'7 38 .7854 39 1.578 1 40 1.9m ! 41 8.741 1 4-i 3.14;J 1 4^> 4.71'^ 44 6.383 45 7.854 46 9A2r, 47 33.50 1 48 15.71 49 18.85 1 50 21. m \ 51 35.i:{ 1 53 28.27 1 5;? 31.41 1 54 ^4.55 1 55 87.70 j 56 40.84 57 43.98 ; 58 47.13 59 50.36 ! 60 63.40 1 61 66.55 1 ' 63 ^9.m i 63 &i.m 64 6o.t^7 65 69.11 66 72.25 67 75.40 68 78.M 69 81.68 70 «4.8?e 71 87.96 91.10 7.3 94.35 74 97.39 75 100.5 76 103.6 7'i 106.8 78 109.9 79 113.1 SO 116.3 81 : Cir. 119.4 133.5 135.6 138.8 131.9 335.1 138.2 141.4 144.5 347.6 150.8 153.9 157.1 j!>0.2 Ui3.3 166.5 169.6 172.8 375.9 379.1 183.3 185.3 188.5 191.6 194.8 197.9 301.0 304.2 307.3 210.5 313.6 316.7 319.9 333.0 336.2 :2?39.3 333.5 ;J38.7 341.9 345 34*<.3 35l*.3 3.54.5 Size To find the Circum. of any . <^r. Bee pagre 74. A roil 0.0333 0.04911 0.19631 0.;J068 0.6013 0.78541 1.763 t 3.343 I 4.909 i 7.068 I 13.566 19.6;J5 38.374 38.484 50.365 63.617 78.64 95.03 113.10 333.73 153.94 176.71 203.06 336 98 354.47 383.5;J 314.36 346 36 380.13 415.48 453.39 490.87 r);^0.93 572.56 615.75 660.53 706.86 ■754.77 804.35 8.55.30 907.92 963.31 1017.9 !1075,2'^ 1 Size. Area. 38 1134.1 39 1194.6 4U 1356.6 •Jl 1330.3 43 1385.4 4:? 1452.3 44 1520.5 45 1590.4 4*; 1<561,J^ 47 1734.*) 48 18u9.6^ 49 1885.7 50 1963.5 51 3043.8 53 313;i.7 53 330a.i 5-i 2390.3 55 .2375.8 .56 34ft3.0 57 3551.8 58 3643.1 59 , 3734.0 60 3.S37.4 61 . 3933.5 63 ;1019.1 6.3 3117.3 64 3317.0 05 3;318.3 66 ;M31.2 67 :3535.7 68 3631.t 69 3739.JJ 70 3848.5 71 :i059.3 73 4071.5 1 73 4185.4 1 I* 4300.S 44i7.» 76 4536.5 1 77 4656.7 78 4778.4 79 4901.t 80 5(3526.6 l--m 5153.1i To fltid Iho jirea of any Circl* Of diameter see pa^e 74. — T36 — INDEX. j'relace 3 The Boiler in General 5 l*umps 27 llie Engine 3f> How to Line an Engine 47 A''alve Motion 68 The Indicator ^^ For Finding H. P. of Engine, with Example. . tjT To Figure a Diagram 7$ For Finding Friction 7S Standard Multipliers, with examples 74 For Finding Contents of Boiler 7-5 For Finding Pressure on Crown Sheet 75 For Finding Quantity ot Water and Coal Used per Horse Power 76 For Finding Contents oi:4 Tjmk — .-.'-M-ik For Marking Tools , . 78 For Chimneys 7vS For Babbitting Boxes and: making Babbitt. ,. . 7i> To Determine Capacity of any Pump. . ... . M> For Safe Working Pressure of Boiler. .. ...... .m-Sl — 137 — — 128 — For Fiiidiu.c^ Pressure Strains of Boilers 81-82 For Iloatiiig Buildings 82-83 F. )!■ l-'iudiiig Horse Power of Boiler 83-84-85 For F i iidi iig- Weight of Square Superficial Foot of Jloiler Piate \Yh&n Tliicknes s is known . 86 For Safety "^'alves SG-87-88 F\)r Machinists 89 For Figuring* tlie Gears to Put on a Lathe 89 For Tempering Tools Used Daily 03 For Tempering Springs ; 95 Adjustment and Setting of Corliss Engine Valves 96 The Dynamo \Yith Example 107-122 The Differeirt Terms Used in Electricity. . . .121-122 For Figuring II. P. of Dynamo 122 For Gold and Silver Plating. 123 For Points for Engineers 124 For Calculating Speed UDd Size of Pulleys 125 A I'cas of Circles 12ft For Ex])lainiiig the Injector. , , -1-^ P. S.— None genuine without my n a ni e here. Books must be flexible, black, alligator, leatiierette binding; red edge and round corners. Send money in ]egislered letter or postoftice order only. P. IT. Z WICKER, WALTER G. KRAFT, Pubi^ishsr, CHICAGO, TI.L.