THE STOKER'S CATECHISM THE STOKER'S CATECHISM BY W. J. CONNOR. [Device] London: E. & F. N. SPON, LIMITED, 57 HAYMARKET New York: SPON & CHAMBERLAIN, 123 LIBERTY STREET 1906 Transcriber's Note: Minor typographical errors have been corrected without note. Variant spellings have been retained. The oe ligature is shown as [oe]. PREFACE. There is no trade or calling that a working man is more handicapped inthan that of a Steam Boiler Stoker; there are no books on stoking; theman leaving his situation is not anxious to communicate with the man whois taking his place anything that might help or instruct him; and thenew man will be shy of asking for information for fear of being thoughtincapable for the post he is seeking; and the transfer takes placealmost in silence, and the new man has to find out all the ways andmeans at his own risk, sometimes at his employer's expense. My object is to instruct that man in his business without his knowingit, or hurting his very sensitive opinion on stoking and other matters;for I am well aware that it is only the least experienced who are thehardest to convince, or instruct--against their will. I have thereforeventured to devise this simple method of question and answer, which Ihave named "The Stoker's Catechism, " which I hope may instruct andinterest him. I will not encumber this preface with my personal qualifications forthis little work--the answers to the questions might suffice. W. J. C. THE STOKER'S CATECHISM. 1. _Question. _--How would you proceed to get steam up in a boiler? _Answer. _--Having filled the boiler with water to the usual height, thatis to say, about four inches over the crown of the fire-tube, I throw inseveral shovelfuls of coal or coke towards the bridge, left and right, keeping the centre clear; then I place the firewood in the centre, throwsome coals on it, light up, and shut the door. Then I open theside-gauge cocks to allow the heated air to escape, and keep them opentill all the air has cleared out and steam taken the place of it; bythis time the fire will require more fuel, and when the steam is highenough I connect her by opening the stop-valve a little at a time tillit is wide open and ready for work. 2. _Question. _--Supposing there are boilers working on each side of theone you got steam up in, how would you act? _Answer. _--I would light the fire by putting in a few shovelfuls of livecoal from one of them instead of using firewood; that is all thedifference I would make. 3. _Question. _--What is the cause of the rapid motion of the water inthe gauge-glass at times? Is that motion general throughout the boiler? _Answer. _--No; air enters the boiler with the feed-water, and thegauge-glass tube being in the vicinity of the incoming water, some ofthe air enters the glass and flies up rapidly through the top cock andinto the boiler again; in fact there is very little motion of the waterin the boiler at any time while working. I have proved this to be so, and in this manner: the boiler cleaners having finished the cleaning, hurriedly scrambled out of the boiler and left several tools they hadbeen using on the crown of the fire-box, namely, a bass hand brush, atin can, and a tin candlestick, and a small iron pail; the manhole coverwas put on and boiler filled and put to work before the things werethought of, and then it was too late and they had to remain there untilthe next cleaning time, which was thirteen weeks; and when the boilerwas at last blown out and the manhole cover removed, the things were onthe crown of the fire-box exactly as they were left three monthspreviously. In order to satisfy myself of this, to me, extraordinarydiscovery, I placed several articles on the crown of the fire-box, things that could not stop up the blow-off pipe if they were swept off, and got up steam as usual, and after three months' hard steaming I blewout the water and steam, took off the manhole cover, and there were thethings as I had left them thirteen weeks previously; of course they wereall coated with fine mud, but no signs of having moved a hair's breadth. 4. _Question. _--But water in an open caldron with a fire under it, as inthe steam boiler, will madly sweep the sides and bottom with terrificebullition. How would you account for the great agitation in the opencaldron while the steam boiler had hardly any, although both vessels hadfierce fires under them? _Answer. _--In the matter of the open caldron the action of the water hasno resistance but that of the atmosphere, whereas in the steam boilerthe movement of the water is resisted from the moment it is heated, forthen a vapour rises above it, and, as the heat increases, the resistanceto the movement of the water is proportionally increased, and as theheat of the steam increases the pressure on the water increasesproportionally all through, the steam being above the water. Any oldstoker knows that when getting steam up in a boiler the lower parts areoften only warm when there may be eight or ten lb. On the square inch inthe upper portions; when the water begins to boil the steam rises in theform of minute globular particles, and remains above the water untilthere is an outlet for it by opening the stop-valve or through thesafety-valve; and as the pressure is the same throughout every part, nook and corner, and angle, there can be no dominating force to causeany agitation within the boiler. 5. _Question. _--What is superheated steam, and why is it used? _Answer. _--If a boiler is placed at a long distance from the engine orwhatever the steam may be used for, there is much or little condensationaccording to the distance and the weather, so that there would always bewater mixing with the steam, and that is most objectionable where asteam engine is concerned, and by super-heating the steam it comes tothe engine as hot and dry as if the boiler were close by; but whateverthe heat of the steam may be, the pressure cannot be increased after thesteam has left the boiler. In proportion to the pressure of steam so isthe heat of it; the higher the pressure the hotter the steam. 6. _Question. _--If your water gauge-glass broke while the boiler wasworking, how would you proceed to rectify the mishap? _Answer. _--By immediately shutting off both cocks, the water-cock first, then I would open the blow-out cock (at the bottom of the gauge-glass)and keep it open to the finish, and commence unscrewing the nuts, clearing them of any bits of india-rubber that adhered to them, also thesockets. Get one of the half dozen glasses already cut, and my string ofrubber rings, enter two rings on the bottom end of the glass, slip thenut over them, slip two rings on the top part of the glass after havingslipped the nut on, and enter the rings in the sockets, then screw upboth top and bottom nuts by hand alternately, and when screwed upevenly, open the steam cock a shade to warm the glass, and when it ishot enough, open it more and commence closing the blow-out cock, bytapping it lightly by hand, then open the steam cock a little more andopen the water cock a little also, and shut off the blow-out cock, andpresently the water enters the glass, and both top and bottom cocks maynow be opened to their full extent, and the job is done. 7. _Question. _--How would you cut a water gauge-glass to the properlength? _Answer. _--I usually cut a piece of iron wire the length the glassshould be, in this way: I measure the length from under the top nut tothe top of the bottom nut, and cut my iron wire to that measurement;then I cut several glasses in my spare time, instead of doing it whenthe glass breaks. I mark a circle where I wish to cut the glass, andwith a three-corner file I run it round this circle to a depth of the16th of an inch, and break it off on the edge of the vice, bench, orother solid woodwork; of course this iron-wire gauge will perhaps onlyanswer for this particular boiler, but in some stoke-hold the boilersare all alike with regard to the gauge-glasses. 8. _Question. _--What is the cause of a vacuum in a boiler? And how doesit affect her injuriously? _Answer. _--The vacuum is mostly caused by letting cold water into a hotboiler, the hotter the boiler the stronger the vacuum; when the water ishotter than the boiler, there will be little vacuum; a strong vacuum inthe boiler will cause the air outside to press on the boiler inproportion--the stronger the vacuum inside, the greater the pressureoutside. In this circumstance the pressure is misplaced for the boilerwas constructed to bear an internal pressure and not an externalpressure. And in getting steam up the pressure on the boiler has to bereversed, and this tends to loosen the plates and rivets and makes herleak, if she never leaked before. I have frequently known boilers to befilled with water over-night to be ready for lighting up in the morning, and have found the gauge-glass empty; this puzzled me at first, but onopening the blow-out cock of the water-gauge the air rushed into it witha gurgling noise, then I knew there was water in the boiler held up bythe vacuum, but I soon altered that by opening the side-cocks, andletting air into her which soon killed the vacuum, and down came thewater into the glass again to the proper level. When getting steam up, Ialways open one of the side gauge cocks and keep it open until steamissues from it; that permits the foul air to escape and prevents avacuum being created; there used to be a vacuum valve in the vicinity ofthe steam dome, that opened inwards and prevented a vacuum from beingcreated. 9. _Question. _--If you had only one boiler and one engine at work, howwould you manage to clean your one fire without letting the steam godown? _Answer. _--When pushed for steam, which usually occurs when the fire isgetting dirty, I get ready all the tools and some of the best of thecoals, and having a bright fire I take the long poker and skim all thefire to one side and throw a couple of shovelfuls of coals evenly overit and rake out all the clinkers on the opposite side, then with thelong poker (some people call it Kennedy) I skim all the fire over to theopposite side and throw a couple of shovelfuls of coals evenly over thebright fire, and rake out the clinkers on the other side, then I spreadthe fire evenly over the bars and sprinkle some more coals over all, andshut the door. This performance from first to last need not take morethan ten minutes, and the boiler was making steam all the time, and atthe finish I had a better fire than at the beginning, and the steamhardly lost a pound; but the job must be done quickly. 10. _Question. _--What is the cause of the humming noise that issues froma steam boiler at times, and how would you prevent it? _Answer. _--It is caused chiefly through bad stoking, in having an unevenfire, full of holes, or crooked bars, the cold air rushing through wherethere is the least resistance, and into the tubes, causes the hummingnoise--a locomotive nearing home after her day's work has very littlefire on the bars and will generally hum, so there is some excuse forher, but none for a stationary boiler. Some stokers take credit tothemselves for making the boiler "Hum"; when coals are thrown into thefire indiscriminately--small and large--the air finds the leastresistance through the small coals, which soon burst into holes, whilethe lumps remain solid; then the air rushes into the holes and thehumming commences; or, if the firebars are not equally separated, theair enters the widest space and the boiler hums; or it may be that thebars next the side of the fireplace are out of line and lets the airrush up against the side and the boiler hums. If the stoker would onlydrop a shovelful of coals dexterously into each hole the humming wouldstop immediately, or level the fire with the rake or long poker, or openthe fire door if the rake is too heavy, and the noise will cease. Thechief point is to have a good set of firebars and well placed; if theyare too long they will hump in the middle or they will bulge sideways;if they are too close together they become red-hot because there is notroom enough for the air to pass between them to keep them moderatelycool, and if they are too short they will drop down into the ash-pit. 11. _Question. _--Why is it more difficult to keep steam-tight themanhole cover of a portable boiler than the manhole cover of astationary boiler? _Answer. _--The portable cover is usually on the side of the boiler, andabout half the cover is immersed in the water and half in the steam; theportion under water is about 212° of heat, the portion of the same coverin the steam is about 500° of heat, the hottest part expanding much morethan the cooler part, and is constantly tending to tear itself away fromthe lower portion of the cover, and the joint cannot stand the unequalstrain. The manhole cover of a stationary boiler is nearly always on topof the boiler, and the heat is equal all over it and no contraction andexpansion to cause the joint to leak as in the portable cover. 12. _Question. _--How would you prepare a boiler for the inspection of aboiler inspector? _Answer. _--I would blow her right out, take off the manhole cover, takeout the safety valve, take out all firebars and the bridge, take downflue-port brickwork, have the boiler and flues thoroughly cleaned andswept, have a lamp or candle ready to light, a hand hammer and chisel, or scraper, a pailful of clean water, and a wad of cotton waste. Whenthe inspector arrives, he quickly dons his overalls; I hand him thelight and the tools and waste, and he is into the fireplace in a jiffy;down the side flues, under the boiler, giving a whack with the hammernow and then, and scraping off any suspicious scale, etc. ; and when hecomes out, as black as any sweep, he slips out of the overalls, givesthem a whack against the wall, folds them up tight, and crams them intothe black bag; has a dive in the pail, and is soon ready to go offsomewhere else. But he tells me something about the boiler before hegoes--not to my discredit. 13. _Question. _--How do you proceed to get her to work again, and whatmaterials do you use? _Answer. _--I first proceed to build the bridge and flue-ports, put inthe firebars, the thin bars at the sides; then I replace thesafety-valve, taking care not to damage it or its seat, fill the boilerwith clean water, put in the boiler the usual quantity of NaenairesAnti-Corrosion liquid, or the powder, make the manhole joint withplaited three-strand spun yarn and stiff putty (red lead and white lead)and lay the fire, which is done in this way: throw a dozen shovelfuls ofcoals towards the bridge, and to left and right of it till they reachnear to the dead-plate, leaving the centre clear for the firewood; thenthrow in three or four shovelfuls of coals over the wood, with oilywaste or paper in front, and she is ready for lighting, and the "fireis laid. " The material for the bridge and the flue ports are firebricksand fireclay; these are rather expensive, but I learnt a wrinkle in thebuilding up of bridge and flues. Through the frequent removals of thesefor boiler inspection and the hitting of the end of the long poker, several bricks were broken every three months, and I came to thedecision to try stock bricks faced with fireclay as mortar; and I wasmore than satisfied with the result, and ever since then I used stockbricks and fireclay only. 14. _Question. _--How high should the top of the bridge be from the crownof the boiler or from the fire-tube? _Answer. _--The bridge should be about nine inches from the crown of thefire-tube, if it were eight the draught would be curtailed, if it wereten the draught under the bars would be diminished, through much airpassing over the bridge instead of under the firebars. As I hadpermission from my employers to build the bridge to the best advantagefor myself in keeping up the steam, and having tried different heightsfor many years, I found that nine inches was the nearest to perfection. And in these experiments two additional bridges were built in oneboiler; six feet behind the ordinary bridge was a concave bridge and sixfeet behind that was a convex bridge. The concave bridge was builtclose up to the bottom of the fire-tube, and resembled a small archway, and extended down to within nine inches of the bottom or shell of thefireplace; the convex bridge was built on the bottom of the shell andreached to within nine inches of the fire-tube. When the flame from thefurnace shot over the ordinary bridge, it clashed down under the concavebridge, then rose up and swept through the convex bridge and away to thebottom flues; the object of these three bridges, in one tube and for onefire, was to keep the flame and heat in the boiler as long as possible, instead of the heat flying swiftly over the bridge and out of theboiler. This experiment seemed to answer very well, but as there wereseveral other boilers connected with this one there was no opportunityof testing it correctly, but the three bridges remained established, andwere frequently shown to engineers and others. 15. _Question. _--What advantage is there in having the blow-off pipe ofa boiler entering it from the top instead of at the bottom? _Answer. _--I am not aware of any advantage in it, but I am aware of adisadvantage in it, and it is this, that while the boiler is being blownright out for the purpose of cleaning, or other reasons, the stoker willoften commence doing some other work, and in due course the boiler isfilled up with water, and the fire lighted, and by-and-by the stokercomes to see what progress she is making; he looks at the water-gaugebut sees no water in it because it has syphoned out of the boiler; atfirst the heated air pressed on the water and forced it through theblow-off pipe, and then the pipe became a syphon, and the pressureincreasing as the water leaves the boiler, she is soon emptied, and ifthe fire is not raked out, soon burnt. Such a mishap could not happen toa boiler with the blow-off pipe at the bottom, for when the stoker blowsout his boiler he must shut the cock before he can fill her, and whenfilled there is no chance of the water escaping out again. 16. _Question. _--Is there not some disadvantage in having the blow-outcock at the bottom of the boiler? _Answer. _--Yes; the cock and pipe are subject to corrosion on account ofwater dripping down on them from the stoke-hold floor, as some stokersquench their clinkers and ashes while they are up against the front ofthe boiler, instead of drawing them forward a few inches from the front:and as the pipe is out of sight under the plates of the floor, nobodytakes the trouble to lift them and examine--not only the pipe and thecock, but that part of the boiler where the water streams down from thedrenched ashes so frequently. So there are disadvantages in both methodsof blowing out the boiler, and always will be, until the stoker learnshis business, and takes an interest in his work, not only for his ownsake, but his employer's also. 17. _Question. _--What is the most important appendage to a steam boiler? _Answer. _--The safety-valve, but it is not always a safety-valve, whenit is weighted to twice the amount the boiler is certified to be workedat safely. As an instance: Amongst the many engines employed at theMidland Extension Works, St. Pancras, was a light steam crane forhoisting earth from the deep excavations, there were in use small woodenskips, and the pressure of steam was forty-five lb. ; but after a timethere arrived large iron skips that the crane could not lift, even whenempty; there were about twenty men depending on the crane for their workand the navvy-ganger was anxious for "something to be done, " and thecrane man hinted about weighting the safety-valve, and no sooner saidthan almost done; the safety spring balance was screwed down, and arailway chair suspended from it by strong copper wire, and the steamallowed to rise until it reached ninety lb. On the inch, and the bigiron skips were hoisted with their load of heavy ballast as easily asthe wooden ones had been. The boiler _happened_ to stand it. 18. _Question. _--Have you any other instance? _Answer. _--Yes; in an establishment in Hammersmith some years ago, thestoker was in the habit of putting a bit of iron on the end of thehorizontal lever of a safety valve when the steam rose too high, and themanager was about, and when it went down he would take off the bit ofiron and put it where he could find it for the next occasion. Themanager had gone away one day, and advantage was taken of it to have alittle carouse in which most of the men took a part; and when the steamrose the stoker popped his bit of iron on the lever and all was quietfor a time, when another noisy safety-valve began to blow off, and onwent another bit of iron that stopped the noise, and during all thistime the fires of seven or eight boilers were burning fiercely, and thestoker should have checked his fires instead of what he had done; but inthe midst of the carouse all the boilers began to belch forth steam whenthe manager came on the scene. The stoker tried to pick off the bits ofiron before the manager could see them, but the steam was to high forthat; and when at last the noise subsided and the steam had clearedaway, the whole of the revellers were on view, caught in a trap, asthere was only one exit. Most of the men were fined or suspended, thebits of iron were discovered on the levers, and the stoker had a week'snotice to clear out, and lock-up valves were fitted on every boiler andthe keys kept in the manager's desk ever after. 19. _Question. _--Can you always depend on the safety-valve lifting whenthe steam rises? _Answer. _--I always keep an eye on the pressure gauge, and if I findthat the safety-valve does not lift at the pressure it ought to lift atI know that the valve is sticking, and I lift the lever and let thesteam out; the cause of the sticking may be that the valve has worn downin its seat and becomes conical, or there may be a shoulder on the valvethat would cause it to stick, or it may be that the lever and fulcrumwere smeared with oily dirty waste in the process of cleaning and notwiped off, but left to bake between the parts, which would prevent thefree action of the safety valve. 20. _Question. _--Why is the safety-valve lifted at times, especiallywhen getting steam up? _Answer. _--It is often done by old stokers as well as new ones, and ismore of a silly habit than of trying the pressure of the steam, especially as there is nowadays a pressure gauge for every boiler in astoke-hold. By lifting the safety-valve while steam is in the boiler anddropping it down again is a dangerous practice; there is a rush of steamto the valve when lifted, and when it drops the rush of steam isinstantly stopped, and rebounds like an india-rubber ball hit againstthe wall, and this commotion within the boiler is likely to blow thestop-valve to pieces or the manhole cover off. Besides that, there isalways dust floating on the surface of the water, especially in a boilerjust cleaned, and when the valve is lifted the dust is carried up withthe steam, and when the valve is dropped the dust is caught under it andoften causes the valve to leak. 21. _Question. _--When the water in the gauge-glass appears motionlesswhile the boiler is working, what does it portend, and how would youproceed to rectify the stagnation of the water? _Answer. _--It portends that the passage for the water is choked andrequires clearing, and I would lose no time in commencing to rectify thestoppage; as a stoker who is responsible for the safety of the boiler Iam always prepared for emergencies. I commence by shutting both cocks ofthe glass, the steam and the water, and unscrew the small bolt in thewater gauge, which is fixed there for the purpose of clearing the tubethat conveys the water to the glass, and with an iron wire in one hand, I open the water cock with the other hand, and push the wire into thesmall hole from which I took the bolt, giving several pushes and pullswhile the water and steam are flying out, until the tube is quite clear;then I withdraw the wire, shut the cock, and serve the steam cock inlike manner; and while I was doing all this the bottom cock of the gauge(the blow-out cock) was open from the beginning. Then I commence to putthe pressure on the glass by warming it with steam from the top cockslowly; then I open the water cock a little, and so on, alternately;then I commence shutting the blow-out cock a little. By theseman[oe]uvres the pressure on the glass is put on gradually instead ofpopping it on too suddenly and breaking the glass, as is often done bythe _more-haste-the-less-speed_ stoker; now I shut the bottom cock andopen the other two, and the water bounds into the glass quite frisky, and the boiler is safe for the present. 22. _Question. _--What would be the consequence if the steam cock of thewater gauge was choked, while the water cock was clear, or vice versa? _Answer. _--The consequence would be most serious for the boiler, as thewater would be forced up into the glass by the steam under it, and wouldmake it appear as if too much water was in the boiler, and the stokerwould proceed in the usual way to blow out some of this, apparently, surplus water; and then watch to see it come down to the working levelin the glass, but he watches in vain--it will never come down. He mightempty the boiler dry, and the water in the glass will be there as longas a breath of steam remains in the boiler to keep it up. And in theevent of the water-cock being choked while the steam-cock was clear theconsequence would be equally dangerous, for the water that was in theglass before the stoppage occurred would remain in it, for the stoppagewould not allow it to drop down into the boiler again; so there it wouldremain, and when the stoker came round to look at his boiler, unless hehappened to notice that no movement of the water was visible, he wouldpass on without further ado, and remain in total ignorance of hisdanger. Hence the necessity for the stoker to blow out his water gaugeevery time he comes in front of his boiler, and if the water enters theglass in a sluggish or dilatory way the cocks need to be cleared of thepartial stoppage, and let the water enter the glass with a rush. 23. _Question. _--Could a boiler collapse without affecting the fusibleplug? _Answer. _--Yes; the tank that supplied the boiler with water leakedbadly, and to stop the leaks a quantity of fine oatmeal was mixed withwater and poured into it, and in due time reached the boiler; butinstead of the oatmeal permeating the whole of the water in the boiler, it never got beyond the parts surrounding the fireplace; it stuck on thesides and top thickly, and was baked hard on them. After a few days thesides of the fire-tube bulged inwards nearly twelve inches, and theboiler had to be stopped and blown out, and the fusible plug was foundto be unaffected--it was one selected by a Boiler Insurance Company, whohad to repair this damage, and the stoker was exonerated from blame, butthere is little doubt that if the plug had leaked the mishap would havebeen attributed to shortness of water and the stoker would be blamed forwhat he did not do, and get the sack into the bargain. 24. _Question. _--Why is it that an injector can force water into aboiler from which the steam comes to work the injector at a greaterpressure than is in the boiler? _Answer. _--The secret of the working of the injector is due to thevelocity of the steam issuing from the point of a conical tube, andwater issuing from another conical tube somewhat larger than the steamcone, and a partial vacuum created in the barrel by the steam and coldwater meeting--as both cones face each other. The cones are about fourinches long, one and a quarter inch wide at the mouths, and about onehalf of an inch at the points. The suction pipe, steam pipe and deliverypipe are about one inch diameter, and the overflow pipe half an inchdiameter, and the water tank three feet below the level of the injector, the space within the barrel might be twelve square inches; the water andsteam cocks are supposed to be always open, and this is how the injectoris started working. The water-wheel is turned partly round, and afigured disc behind it indicates the quantity of water let into thebarrel, while the steam is let in by turning a wheel attached to aquick-screw spindle; then there are ructions inside--the steam and waterhave come together, and the water overflows through the half-inch pipe;but by a little manipulation of the water, air will soon start itworking; then the overflow ceases, and the air rushes into the pipe andhums, and the injector is working. And the reason of its working is, inmy humble opinion, the concentration of water and steam, with the vacuumthrown in, that gives additional pressure to the water in the injector. I might venture to say it gives fully ten lb. On the square inch overand above the pressure of steam within the boiler. 25. _Question. _--The noise created by the injector while working beingvery objectionable, could it be mitigated? And, if so, how? _Answer. _--Yes; I succeeded in quieting an injector in one establishmentwhere anything louder than the scratching of a goose-quill wasconsidered a nuisance. I first began by putting a piece of paper againstthe mouth of the overflow pipe while the injector was working, and thenoise ceased, but soon after that the paper was sucked up into theinjector. I then applied a leathern disc, which answered well, andproved just the right thing; sometimes the water blurted out, but notoften, and the leathern disc was permanently established; but theinjector would not work with water above 100 degrees of heat; so I wouldstart with cold water and gradually turn on the hot water and shut offthe cold, and she never noticed the change, but the noise was stopped. 26. _Question. _--How would you quiet a noisy pump--one of those stuck upin a corner of the stoke-hold that can be heard, but not often seen? _Answer. _--I had one of them once--a very good little "Manchester DonkeyPump, " but as noisy as they make 'em--and it became a question whethershe should be discarded for an injector; she was bolted to a wall in thebasement of a block of offices and could be heard throughout thebuilding, and my employer told me that he would willingly give a 5_l. _note to anyone who would stop the noise. The donkey was vertical; I tookoff both valve covers and drilled a 3/8-inch hole in each projectionfrom the cover that gave the valve its lift, and drove a wooden peg intoeach hole from the under side, and rasped them down to give the requiredlift, and put the covers on again and started the donkey, and after somemore raspings of the plugs I started her again, and this time wassuccessful; she worked like india-rubber, no noise whatever, and Igained more than was offered to quiet her--a cheque of 21_l. _ Thishappened in Draper's Gardens, Throgmorton Avenue, E. C. 27. _Question. _--When several boilers are working in a row, and one ofthe middle ones has to be cleaned, what would you do to keep it coolenough to enable the men to do the cleaning, and also to protect themwhile in the boiler? _Answer. _--Having blown her right out I would take off the wheel of thestop-valve spindle, tie a piece of canvas on the top of the spindle andlock the wheel up, so that no one should open the stop-valve while themen were in the boiler. Many dreadful things have happened through somethoughtless or meddlesome idiot opening the stop-valve while men wereworking in the boiler. I also cover the blow-off cocks of the boilers insteam, as there is usually a pipe into which the steam and water iscarried off running parallel with the cocks, and take charge of thespanner used in opening them, in case an absent-minded stoker mightattempt to blow some of the muddy water out of his boiler when the menwere in the empty one, and scald them to death, the steam rushing upthrough the blow-off. I then fill the boiler up with cold water severaltimes, and allow cold water to play into the boiler from the manhole bymeans of the hose pipe, and the blow-off cock being open there is alwaysa cool atmosphere for the men to work in; they can remain longer in theboiler, do twice the amount of work, and in less time than in ascorching atmosphere. When the cleaning is done and the boiler rinsedout, I shut the blow-off cock and fill her with clean water to the usualheight; take off the canvas on the spindle, replace the wheel, and theboiler is ready for lighting up the fire. 28. _Question. _--Does familiarity with one's work as stoker sometimeslead to carelessness and then to mishaps? And, if so, give an instance? _Answer. _--Yes; familiarity in doing things frequently during work, tends to a careless off-hand style of self-importance that has oftencaused trouble and mishap. A crane driver employed at the MidlandRailway Extension at St. Pancras, came to work one winter's morning andthe steam being already up, turned it on to warm the steam chest andcylinder, preparatory to commencing work for the day, forgetting that ithad been freezing hard all night, and split the steam chest to pieces. His plea of defence was that steam had remained in the chest andcondensed, and become ice, then expanding, burst the steam chest; thisplea served all right, but the following summer he was less successful. He came to me during the dinner hour and said, "Jack, I can't get anywater into my boiler, will you come over and look at her?" I did goover, and on looking at the water gauge saw it was empty, opened thecocks, but dry steam came forth, opened the fire door and found a brightfire of coke; while the engine was pegging away to get water into theboiler. I said, "Bill, stop your engine and draw your fire at once, andmy name's Walker. " I went back quicker than I came; and an hour laterhe came over to me looking very down, and said, "Jack, I've done it. " Iknew what he meant and went over with him to look at the boiler. It wasas complete wreck, and I told him to fly off and get any money that wasowing him before he got locked up; he did go, and I never saw him since. This man was an engine fitter before he took to engine driving--poorfellow, I was very sorry for him. Another instance. A stoker had to filla boiler and get up steam in her one Sunday morning, there was a bigtank over the stoke-hold from which water was taken to fill coldboilers, a two-inch pipe with stop-cock led to the top of each boilerfrom the bottom of the tank. But the tank was empty on this occasion; adonkey pump close by was used to keep the tank filled, but this boilerwas the one from which the donkey took her steam, and was now empty, butthe stoker solved the puzzle: a boiler with steam was in use about fiftyyards away, and having a steam-pipe connection to the empty one heopened the cock and commenced letting the steam into her, but it wascondensing as fast as it went in; and being one of the extra cleverones, he lighted a fire in the grate so as to stop the condensing, anddid stop it, and let in sufficient steam to work the donkey-pump andpartly filled the tank, and was proceeding to open the two-inch coldwater pipe when one of the workmen passing by saw some cotton wastesmoking strongly on top of the boiler, which induced him to open thefurnace door, and he saw that the boiler was red-hot and collapsed; herushed up to the stoker who had his hand already on the stop-cock to letwater into her when he was forcibly pulled away from it, much againsthis will, but when he saw the damage he had caused he sheered off and wesaw no more of him. This case occurred at the London Hydro-Carbon OilWorks, Southall, W. One more: On a Sunday morning a stoker came in tobreak the joint of a manhole, empty the boiler and fill her up againwith water. After taking the dogs off and securing the cover fromfalling into the boiler, the stoker gave the cover a tap with the end ofthe spanner to loosen the joint, but the cover showed no signs ofslackening, and the end of a crowbar was requisitioned but withoutresult; and in this case, as in a former one, my opinion was solicitedas well as help. I used the crowbar end harder every blow; when at lastthe cover seemed to spring downwards and upwards, I dropped the barinstantly, thinking the devil had a hold of the cover. After a moment'sthought I went down into the stoke-hold and opened one of the gaugecocks and steam rushed out; there were no pressure gauges in thisestablishment; every one of the twenty boilers had eight weightssuspended from the lever of the safety-valve, each weight representingfive lb. Pressure. I took off the weights one by one, and when five ofthem had been removed steam began to blow off, showing that fifteen lb. Pressure was in the boiler while I was trying to knock the manhole coverin. On inquiry it transpired that the man whose duty it was to blow outthis boiler the previous day asked his mate to do it, and the mateforgot all about it (it being Saturday night), and these omissionsnearly caused a catastrophe. This occurred in Pimlico, S. W. 29. _Question. _--What advantage to the employer is the self-actingstoker for steam boilers? _Answer. _--He can use the very cheapest and smallest coals; the cold airis never permitted to enter the boiler; there is no cleaning out fireswith the door wide open; the steam is more uniform in pressure; theboiler will last longer, and little or no smoke. There is a drawback tothese advantages: there must be a live stoker to keep the automaticstoker up to its work; he has to keep the coals supplied to the "Jacob'sLadder"; he has to regulate the supply of coals to the boxes over eachboiler, and regulate the supply of coals dropping down into thefireplace, regulate the speed of the travelling furnace by means of theratchet, clean out the ash-hole of clinkers every two hours and wheelthem out of the stoke-hold, regulate the water-supply to the boilers, and keep the steam at the proper pressure, and rectify any and everyderangement and mishap that occurs to the self acting stoker. 30. _Question. _--But are not these "self-acting stokers" smoke consumersas well? _Answer. _--The self-acting stokers have to be kept working by the livestoker, and are smoke consumers so long as the coals let down on thetravelling furnace is exactly proportionate to the requirements of it, but if the supply should exceed what is necessary, the grate becomeschoked with coals and has to be cleared of some of them, and in doingthis with coals partly burnt, smoke is inevitable; and if the supply isinsufficient, the grate becomes bare of fuel, and cold air finds its waythrough the bars and checks the steam. To remedy this, the coal is letdown and carried onward by the moving grate before they can be ignited, and soon begin to smoke, so that in these two extremes, too much or toolittle coals will cause smoke; but if this type of furnace is in chargeof a competent stoker, there is little chance of the bars being chokedwith coals, or starved for want of them. 31. _Question. _--Is it not possible to consume the smoke of a boilerfurnace independent of patents and mechanical contrivances that canonly be worked by an experienced stoker? _Answer. _--I have proved it possible where several boilers wereconnected and working, and using small and smoky coals. In anestablishment in West London the system in vogue was in this manner: allthe bridges were built hollow, and an iron flap covered the bottom ofthe bridge, and a long iron rod from the flap was carried to the frontof the boiler, and an inch steam pipe with cock attached entered thefireplace above the door, and was joined to a two-inch perforated pipethat was fixed from left to right over and above the dead-plate. Whenthe fires required replenishing, the flap was opened, then the door andsteam cock, and six shovelfuls of coals were hastily thrown in evenlyover the fire, and the door was then shut. The result of thisperformance was a mixture of steam and smoke observable at the chimneytop, the steam was kept on while any smoke was visible; then the nextboiler was served in like manner, and was a continual round of work tothe exclusion of other things. This method prevailed for many yearsbefore I came on the scene, and noticing that a great quantity of steamwas wasted for the purpose of hiding the smoke, and the six shovelfulsof coals hardly compensated for the steam spread over them, I inducedthe man who built the bridges, after inspection, to build them solid, and then I commenced a new method of firing, in this manner: I sprinklethe small coals with water from a hose-pipe, and burn one fire down low, but bright; I shut the damper nearly close and commence firing towardsthe bridge and sides, until the grate is full nearly to the crown of thefireplace, allowing the gas to remain in the furnace and flues fortwenty minutes, then I open the damper a couple of inches; by this timethere are numerous jets of flame flickering all over the coals, and nowI open the damper to the full extent and I soon have a rousingsteam-making fire. I serve the next low fire in like manner, and so on. But it is necessary always while burning one fire down for the purposeof banking it up, to have all the other fires in good condition andcapable of keeping up the steam independently of the one to be bankedup; if the others should burn down too low before one of them is banked, smoke will follow the neglect. I remained several years in this employ;my method was very successful, with proper care and watchfulness, andwas adopted in a similar establishment in South London. The formerestablishment was the West Middlesex Water Works, and the latter theSouthwark and Vauxhall Water Works. One ton of Welsh coals was allowedevery twenty-four hours to get the seven fires up after cleaning. Hereis another method for consuming the smoke, but is a very wasteful one;four or five shovelfuls of small smoky coals are thrown on or near thedead-plate, where they remain until they become sufficiently heated toignite, and are then pushed on to the bars by the rake, and a similarquantity again thrown on the dead-plate, and when ignited pushed on tothe bars as before, and so it is continued. It is expected that thesmoke while passing over the bright fire towards the bridge will beignited, but only a very small portion of it becomes flame, and thesmoke tends to deaden the bright fire to a great extent. The door has tobe opened so frequently in this method, and in pushing the coals fromthe dead-plate to the bars a large amount of live fuel drops down intothe ash-pit, and if this should be thrown into the furnace again, thefire is deadened immediately. There is no economy in this method, whichI tried years ago but never continued since. 32. _Question. _--Is there any difference, and if so, what is it, inlocomotive and stationary boiler stoking? _Answer. _--There is a wide difference between the methods, not only offiring but of the general work of the firemen and the stoker. (I cannotsee why one should be called stoker and the other fireman, for theyboth have to keep the fire going and the steam up). The loco. Firemanhad to be at the engine shed forty-five minutes, and the driver thirtyminutes, before the time of the train starting; the fireman gets thestores necessary for the journey, such as oil, tallow, cotton waste, yellow grease, and perhaps fog signals, gets his lamps from the lamproom already trimmed--these are the head lamp, side lamp, water gaugelamp, tail lamp and hand lamp; he places the head lamp on the right handside of the buffer plank, the side lamp on the left side of the tender, the gauge lamp close to the glass, the tail lamp behind the tender; hehas to take his engine to be coaled (it used to be coke in my early dayson the L. & N. W. R. ), and fills his tender with water, and brings hisengine over a pit, fills the axle-boxes of engine and tender; by thistime the driver shows up, and goes under the engine and thoroughlyexamines every part of the gear; then he oils her, and both men sign onfor the particular train that the engine's number is in line with, andrun down the incline to Euston, where they hook on to their train andwait. If it should turn out to be a particularly heavy train, the driverwill request the pilot-engine driver to hook on and go perhaps as far asTring or Wolverton with the train, otherwise the pilot will detach atthe top of the incline at Camden; if it should be a night train, withthe pilot in front, it is an experience never to be forgotten by a youngstoker. (I was not far in my teens when I had this experience, but anold man now). And at last the signal is given us to start; we blow thewhistle and off we go, two engines panting, puffing, sending up showersof sparks, and soon we leave Camden behind, and by the time we reachWatford we are travelling about fifty miles an hour; this is the speedto test the stoker who has to light his lamps the while, travel roundthe foot-plate and keep his balance, and replenish his fire and climbthe tender frequently; but the passenger trains are a luxury incomparison to the luggage trains. The luggage engines being bigger andstronger than the passenger engine requires more steam and water, because she has more than double the load to run with, and at thestations wagons have to be shunted frequently and often re-shunted; someare left and others taken to far-off places; the guard's van has to bedetached always in order to have it at the end of the train; the stokeris hard at work with the brake putting it on and off, jumping down tohold the points, or coupling wagons--this is not his business, but hedoes it to facilitate the work. When the luggage train had to get into asiding to let a passenger train go by, there was no pit (except at astation) for the engine to stand over, and both men would have to crawlunder the engine to do anything necessary, through wet, or snow, or mud;and when starting the engine out of the siding or from a station, andthe driving wheels slipping round, the stoker had to jump down with hisshovel and scrape up a bit of gravel, or sand, or clay, and pop it onthe rail in front of the driving wheel, and if that should stop theslipping, the engine gave a bound forward and the stoker had to run tokeep up with the engine, throw his shovel on to the foot-plate, andscramble up the best way he could, or be left behind. In bad weather, ifit rained, hailed, or snowed, both driver and stoker had to keep alook-out by holding their hands up before their eyes and looking betweentheir fingers; when it rained, and one side of each man was wet through, they would change places till the other side got wet through also. Thesewere the good old times. Drivers and firemen in the present time maythank their stars that the way was well paved for them before theystarted. So there is hardly any similarity between a stationary boilerstoker and a locomotive stoker, except keeping the steam up perhaps; theloco. Stoker is the king of all stokers. 33. _Question. _--How is the stoking done on a big steam ship? _Answer. _--In a Royal West Indian Mail Steam Packet, in which I wasstoker, there were forty-five stokers and coal trimmers, forty-fivesailors, besides a number of stewards, stewardesses, six engineers, sixship's officers, several mail officials, butchers, bakers, and a brassband of eighteen musicians. There were two stoke-holds, one fore and oneabaft the funnel, and four boilers in each, and four furnaces in eachboiler, and three stokers in each stoke-hold, also three trimmers ineach stoke-hold. There was the same method of working in bothstoke-holds, and a constant and continual round of firing kept up dayand night. When going down on watch I have a piece of waste in each handto protect them from the hot handrails; I commence work by cleaning thesmall tubes of four furnaces, then clean out the four furnaces, rake outthe ashes from the pit and fill them and the clinkers into iron buckets, which the sailors haul up and empty over the ship's side. And while I amengaged in this work my two mates are doing my firing for me--which isin this way: one man fires every other fire of the sixteen fires, thengoes round again and fires those he missed the first round, then hismate takes the shovel from his hands and fires every other fire, thenfires those he missed the first round; the third man does likewise, andso it is constant firing all through. And having towering hot boilersboth sides of us and roaring furnaces behind and in front, the sweatpours from us continually, and we are glad to pop into the engine roomafter firing to get a draught of somewhat cooler air. I happened to havethe middle watch--12 midnight to 4 a. M. --which is the worst of thewatches, for when I came off at four the hands on deck were always doingsomething to make a noise, and there is little chance of getting asleep, and hammocks must be stowed away before eight; then breakfast, and the brass band strikes up for half an hour; but if there had beendog-watches all of us would share in the middle watch--as follows:-- Brown Morning Watch 4 to 8 a. M. Jones Forenoon " 8 to 12 noon. Robinson Afternoon " 12 to 4 p. M. Brown First Dog " 4 to 6 p. M. Jones Second Dog " 6 to 8 p. M. Robinson First " 8 to 12 midnight. Brown Middle " 12 to 4 a. M. Jones Morning " 4 to 8 a. M. = 24 hours. A few hours after leaving Southampton all hands are mustered andapportioned to man the seventeen boats hanging from the davits, eight oneach side, and the captain's gig under the stern; after this ceremony weget an allowance of grog. The fires are now beginning to be dirty, having clinkers seven or eight inches thick, which are not allowed to bepulled out until the whole fire is cleaned at the usual time; thisorder from the chief engineer surprised me at the time, as clinkers arenot calculated to increase the steam, so I left them there to deaden thefire, but later on I found the solution; I was told by an old stokerthat there was sharp competition between the chief engineers as to whocould do the voyage at the least expense of coals, and that informationexplained the action of our chief engineer who would often perambulatethe deck till midnight, watching the windsails that they should remainwith their backs to the wind in order to prevent a breath of cool airreaching the fires, that would cause them to burn a few more pounds ofcoals, while some of the stokers were often hauled up in the ash-bucketfainting from the stifling heat of the foul-smelling stoke-hold. We wereall supplied with fishing-lines and hooks of three different sizes, andextra grog when getting steam up. The method of cleaning and polishingthe engines and all bright work was very effectual, and did the stokersgreat credit; after having scoured and polished the steel and brightironwork they were frosted, in imitation of hoar frost. A pot of hottallow and white lead in which a clean piece of cotton waste was dipped, and the parts smeared evenly in line with the metal, and when this driedit was dabbed, or patted, with another clean piece of waste also dippedin the hot tallow, which gave the metal a good imitation of hoar frost;the brass and copper work were burnished and shone like gold. The boatdrill and fire drill create some wonder for the passengers, as theyalways happen unexpectedly; the former begins in this way: a large gongis rapidly hit with a mallet by the quartermaster, and all those stokersand sailors, who belong to the seventeen boats hanging from the davits, immediately make their way towards them and commence to clear the falls, and the word is given to lower all boats, while the men hold their oarsready to push off, and the boats are run down nearly to the water'sedge; then it is up all boats, and those on deck run them up in a jiffyto their places under the davits, and coil the tails up, and this endsthe boat drill. The fire drill takes place on another day, and commencesin this manner: the ship's bell is rapidly rung by the quartermaster;the unusual rapidity of the ringing attracts the attention of all thepassengers who commence to crowd the upper deck; the stokers drop down adozen hose-pipes on the deck and run them out straight, and screw themto nozzles leading down to the engine room. The engineers pop the pumpson and up comes the water; every hose is now stiffened and the branchesare all directed over the ship's side, where they make a grand display. All those of the ship's company who take no watches, as cooks, stewards, bandsmen, etc. , have each a pail full of water in hand, others ablanket over their arm, all in exact line, and ready to help ifrequired; and after a few minutes' display of the hose-pipes, theboatswain's whistle ends this drill for this voyage, and the hose-pipesare disconnected, rolled up, and hung up, to be ready at any moment ifrequired. There are plenty of amusements on board, such as single-stick, glove-boxing, wrestling, etc. But the game of the "Man in the Chair, " isone of the most laughable. A piece of board, 12 inches by 18 inches, inwhich a strong rope is inserted in a hole in each corner and knotted onthe underside, the four ropes are carried upwards and made fast to theforestay, and the "chair" has to be 6 feet from the deck. There areperhaps thirty stokers in this game, and each one has twisted his blacksilk neckerchief into rope shape, and a volunteer sits on the chair, holding on to one of the chair-ropes with one hand and in the other hissilken rope. During these preliminary tactics the passengers arecrowding round to see what may happen. At last the man on the chairgives the word "Ready Boys, " and then commences a real slogging match, hitting the chairman on legs, arms, face, neck, anywhere they can hithim, and every hit being a matter of chance the passengers roar when theman in the chair delivers a stinger to his tormentors; his blows comewith double force, as he is high above them, and swinging round andround, and to and fro, they come unexpectedly and cause roars oflaughter; while this is going on a little tub, called a spitkin, issurreptitiously pushed in view, and a few silver coins dropped into itby one of our men, which causes the audience to dip their hands in theirpockets and a few pounds in silver are quickly thrown in; and after halfan hour's play this game comes to an end. One more specimen of the manygames that delight the passengers: about twenty men stand close togetherand in line, their faces to the ship's head, the front man has a bandageon his eyes, any one in the rank is at liberty to step out and go up tohim and slap his cheek, and dart off to his place in the rank before theblindfold touches him; if he does, the touched one has to don thebandage, and the other pulls his bandage off and takes a place in therank. When the slap is delivered, the slapper darts back to his place inthe rank with all possible speed, and the slapped one darts after theother like greased lightning, and touches the wrong man perhaps, andpulls the bandage off, only to have to put on again, while thepassengers roar with delight; the little tub is not forgotten in thisgame; and then the climax comes when we think the blindfold has hadenough of it, and when a burly stoker steps out to deliver his slap, therank closes up tightly, and on rushing back to his place with theblindfold at his heels, and the wild exertions of the man to squeezehimself into the rank before he is touched and the joy of the blindfoldwho has just touched his man, creates loud cheers and laughter, and theburly man has to don the bandage and take his stand in front. Beforearriving at St. Thomas, there is a general clean up, bilges pumped out, engines cleaned, boiler fronts and lagging polished; the passengers arepreparing for another voyage to some of the islands further west, asTrinidad, St. Vincent, Barbadoes, Martinique, St. Kitts, St. Lucia, etc. On entering the harbour guns are fired in our honour, and we return thecompliment by firing our six-pounder from the forecastle, the Colonialsteamer comes alongside our ship, when there are cheers and waving ofhandkerchiefs and handshaking; the bumboats come alongside also and manypeople, and board our ship, offering us a great variety of things forsale; women galavanting over every part soliciting the officers'washing, etc. , etc. Our engines receive a thorough overhaul, boilers arecleaned, cabins and stairways painted, and all bright metal cleaned andrepolished; our coals are delivered on board by a swarm of men, womenand youths, of both sexes, carrying them in small wicker baskets ontheir heads, and stepping on a scale or counter on their way to theship, the process occupying about three days for about 800 tons of Welshcoal. At last the time has come for starting for home; all visitors areordered off the ship: moorings are cast off, and a man at the voice-pipespeaks to the engineers down below, and the great paddle-wheels revolveslowly for a minute, while the band strikes up some appropriate air, as"Afloat on the Ocean my days gaily fly, " or "Afloat on the Ocean Wave. "Then commence the wild cheering and waving of hats and handkerchiefswhile the great paddles have lashed the water into white foam, and weare fairly off for a fourteen days' voyage home. In all our games onboard in which I took part I noticed the distinguished presence of ourhighly respected captain, which I am sure greatly enhanced our takingsin the little dish. 34. _Question. _--How is a hydraulic pump constructed? _Answer. _--There are various sizes, ranging from a 1/4-inch to 4 inchesin the diameter of the plunger or piston, as it is sometimes called; thelarger size would be constructed in this manner; the barrel of the pumpis 3 feet long, and on its top, and in line with it, and in the samecasting, an air chamber is situate into which water and air enter atevery suction of plunger, and serve as a buffer or cushion in thedelivery stroke. The spindle of the plunger is connected to the pistonof the steam engine by a hole and stuffing box in the cylinder cover, and a connecting crosshead secures the spindle of the plunger and theextra piston, so that would bring the crank of the engine, theconnecting rod, piston, extra piston, and plunger all in a straightline, and a direct stroke. About 6 inches of the plunger is occupied bythe packing at the outer end; a solid ring of iron an inch wide, and aninch high, and securely pinned to the plunger, has a leather cup pushedon to it, then a loose ring is slid up against the back of the leathercup and another cup, and another ring, until the space for the packingis filled up; then a nut is screwed up behind these which brings cupsand rings tightly together, and a jam-nut with a split-pin going throughnut and spindle and opened wide enough to clear the sides of the barrel, and the hydraulic pump is ready for work. 35. _Question. _--How is a hydraulic accumulator constructed, and why isit necessary? _Answer. _--By having an accumulator, a lift, crane, or press, workssmoothly, as there is a steady and smooth supply of the power; whereaswithout it, the lift, crane, or press, would work in jerks or jumps;with every stroke of the pumps there would be a jerk; it would be anintermittent not a continual power. The accumulator consists of acylinder of cast iron about 9 feet in height, 4 feet outside diameterand 3 feet internal diameter; it rests on massive oaken timbers about 4feet from the ground; inside the cylinder is a ram 9 feet high, also 2feet outside measurement, and 12 inches diameter inside; it islathe-turned, smooth and bright; four slabs of cast iron, each a quarterof the circumference of the base of the cylinder, are placed over foursteel bolts that have to support the dead weight, each bolt being about12 feet high, 4 inches in diameter, with square necks and flat heads, and a hole in each slab to receive the bolts; the flat heads of thebolts are to facilitate the accumulator resting level on the oakentimbers; the slabs would be 2 tons each. On the slabs are fixed smallsegments all round and round the base of the cylinder until the requirednumber (perhaps 150) is placed one on top of the other, each segmentweighing 2 cwt. ; then the crosshead is placed over the top tier, andhaving a hole in each of its four arms it is entered on the bolts whichhave a screw-thread; the nuts are put on and screwed up tightly, and theaccumulator is erected. 36. _Question. _--How is the accumulator started working? _Answer. _--The engines are started pumping into the ram and cylinder, whose drain-cocks have previously been opened, and air and water issuesfrom them; when the air has escaped they are shut off, and then thegreat mass of iron and steel begins to tremble and totter and movesupwards and upwards, and on nearing the limit of its journey the top ofthe accumulator lifts a projecting lever which has a small chainattached to it, the bottom end of the chain is attached to the steamthrottle valve, and when the chain is pulled up at the top the steam isshut off at the throttle-valve and the engine stops, but will start assoon as any water is taken from the accumulator. 37. _Question. _--Is there any similarity in terms used in hydraulic workand steam boiler work? _Answer. _--There are several terms common to hydraulics and steam; thesteam boiler might be called an accumulator of power; there is aslide-valve in hydraulics as in the steam engine, to admit the power andto allow the exhaust to escape; there are stop-valves and intermediatevalves in hydraulics, as in steam pipes, also air-vessels in each: thereare suction and delivery pipes and valves in each, and relieve valvesalso in each; there is a cylinder in each in which the power isconcentrated; there are reversing levers in a hydraulic crane, as in asteam crane. 38. _Question. _--Who invented the atmospheric engine, and how was itconstructed? _Answer. _--Savory, a mining agent, invented the first method, which hecalled an engine, of drawing water up from a well by means of a vacuumwhich he happened accidentally to discover a method to create, and thepressure of the atmospheric combined with it. He procured a real steamboiler with a safety valve and gauge cocks and erected two vessels inwhich to create a vacuum; a suction pipe from the bottom of each vesselled down into a well beneath the vessels, and a valve that openedupwards was on the end of each pipe. When about to start work, steamfrom the boiler was turned into one of the vessels, and kept on until itwas as hot as the boiler itself, while a drain cock was kept open thewhile, and when air and water had been forced out of the vessel steamwas shut off, and water from a tank above the vessel was allowed to flowon it, which soon made a vacuum inside the vessel, and water was suckedup through the valves opening upwards and delivered into a tank placedfor the purpose. While this performance was in progress, the othervessel was being charged with steam to repeat the performance, etc. Thisis the extent as far as I know of Savory's claim to be the inventor ofthe atmospheric engine. 39. _Question. _--Who was the real inventor then? _Answer. _--Newcomen and his partner Cawly adopted a working beam, thatis, a beam working on a centre or trunnion. At one end of the beam wasthe pump, at the other was an iron cylinder with an iron piston in it;both ends of the beam were arched or sexton-shaped, and had a chain oneach, one connected to the pump rod, the other to the piston rod. Whenabout to start work, the piston being up near the top of the cylinder, steam was let in under it and a jet of water was let in which sooncondensed the steam and created a vacuum within the cylinder, and thepiston was drawn down to the bottom and the pump drawn up with its loadof water; and a counter weight was attached to the pump-rod to alwaysbring the piston to the top of the cylinder after each descent. This isa very brief description of this atmospheric engine; there were now onlytwo cocks to open and close--the steam cock and water cock, and theengine only required a boy for this purpose, but the boy himself added ashare in this engine. In order to have a relief from the monotony ofopening and shutting the cocks alternately, he tied strings to thehandles and then connected to the working beam in such a manner that thecocks were opened and closed exactly at the nick of time; this causedthe engine to work far more regularly and to do twice the work it haddone previously, the boy's name was Humphrey Potter. 40. _Question. _--What did James Watt do in connection with theatmospheric engine? _Answer. _--Watt being a mathematical instrument maker, was requested torepair an old engine used by some students of Glasgow University; havingfinished the repairs, and in working this model (the best type of theatmospheric engine), he found and proved by many and variousexperiments, that an enormous waste of fuel was absolutely necessary inworking the engine; he found great difficulty in keeping the air fromentering the cylinder, and the cylinder top was so exposed to theatmosphere that the steam was much condensed when it entered thecylinder, and he came to the conclusion to put a cover on the top of thecylinder, and allow the piston-rod to play in a hole in the cover with agland and stuffing box, and _to press down the piston with steam insteadof the atmosphere_. This engine was no longer atmospheric, it was a realsteam engine, the first ever seen or constructed, for steam was used tocreate the vacuum, and steam was used to work the piston; but this wasonly the beginning of his great improvements. This engine thoughsuitable for the purpose of pumping water, was totally unsuitable forcontinuous rotary motion, the steam acting only on the downward strokeafter the piston had been pulled up to the top of the cylinder by meansof the additional weight fixed on the pump end of the beam. He devised amethod to admit steam under the piston as well as above it, but theflexible chains although suitable for the down stroke of the piston werepowerless in the up stroke, they would hang listless and useless. Thisbeing so, he determined to get rid of the chains at both ends of thebeam, and also both arched ends, and substitute a ridged connection atboth ends of the beam. He put an iron connecting rod from the end of thebeam to the pump rod, and the other end of the beam was connected to thepiston rod by a crosshead; to this engine he attached that grandappendage the "Parallel Motion" which is the pride of the beam engine upto to-day. He devised the improvement of the separate condenser for theexhaust steam, instead of the jet of water under the piston. He inventedthe crank for his engine, also the sun and planet motion, also thethrottle valve, also the counter to indicate the number of revolutionsthe engine had performed, also the "Cut off, " the steam moving thepiston by expansion when it was cut off at one-third the length of thecylinder, and thus saving two-thirds of the steam and a more uniformrate of speed. 41. _Question. _--Give a description of the Sun and Planet method, andwhy he invented it? _Answer. _--The sun and planet were two cog-wheels geared into eachother, the sun being 3 feet diameter and the planet 2 feet diameter, thelatter was keyed tightly on the bottom end of the connecting rod, andthe sun which was keyed tightly on the end of the shaft, that was torevolve and work the machinery. But although this method did make themachinery revolve, it was not smoothly, for when the planet wheel was ateither top or bottom of the sun wheel, the power of the engine was lesseffective than it was half way in the opposite positions. This led Wattto add a large wheel on the shaft of the sun wheel, called the flywheel, which equalised the rate of motion to uniformity. Watt inventedthe crank for his engine, but one of his men gave the tip to an engineerat Bristol, who forthwith took out a patent for it and forestalled Watt, who had to invent another means--the sun and planet. But when the termof the patent expired, Watt resumed the crank method instead of the sunand planet, which was noisy, the wear and tear very great, and alsoexpensive. 42. _Question. _--What other things did Watt do towards the perfection ofthe steam engine? _Answer. _--He added the air pump to his engine to draw the condensedsteam and water from his separate condenser; he invented the throttlevalve and the governor, in order to sustain a uniform rate of speed inthe engine, whatever pressure of steam might be on, or variation ofwork, whether heavy or light. 43. _Question. _--Why is the power of the engine called horse-power? _Answer. _--Before the invention of the engine, horses were employed inmills and mines, and other places; the number of horses employed in amill or mine, indicating the amount of work going on, and the necessityof employing them, and when the steam engine came on the scene, and apurchaser wanted, he was told that the engine was equal to so manyhorses; that comparison gave the purchaser a clear idea of the engine herequired. Savory was the first to suggest this comparison, but Watt knewthat horses differed in size and strength, and in order to be sure of asafe standard for his engine power he experimented with big horses insome London breweries, and after careful calculation and comparison hefixed a horse-power at 32, 000 lb. , that is to say, that a horse couldlift that weight of water one foot above the ground in a minute foreight hours per day. This standard has remained ever since, although itis above the average of the power of the average horse, it is in favourof the purchaser of an engine, as well as being capable of working morethan eight hours a day, or twenty hours if required. 44. _Question. _--What is meant by "nominal horse-power"? _Answer. _--It is a rough and ready way of giving some idea of the powerof an engine or engines on the basis of the number of inches in the areaof the cylinder or cylinders, but when the process of taking the diagramof the engine is gone through the term nominal is dropped, and indicatedhorse-power is then expressed, because it was proved by actualexperiment and certainty. 45. _Question. _--How is that performance accomplished? _Answer. _--In horizontal engines there are generally two gun-metalscrew-plugs on the top of the cylinder, one over each end and in frontof the piston; when a diagram is to be taken, these plugs are taken outand other screws put in their places, to which a copper pipe isattached; the screw plugs are 1 inch in diameter, also the copper pipes;and exactly mid-way on the copper pipe is a small cylinder which moveson a pivot, by means of a string with a turn round it. One end of thestring is fixed by a clip on the connecting rod, the other end anywhereto keep the string tight, so that by the movement of the steam enteringthe cylinder at either end, and the connecting rod working backwards andforwards, the small cylinder is made to turn frontways and backways; andwithin the small cylinder is another cylinder very much smaller; it hasa tiny piston within it, and as the steam presses on the little pistonat every stroke of the engine, a pencil from the outer cylinder is fixedin a slot and marks the movements of the little piston on a roll ofprepared paper, slid over the inner cylinder for that purpose, thepencil being kept up to the paper by means of a small steel spring. Thisdiagram on the paper cylinder, not only is used for determining thepower of the engine, but for detecting any irregularity in theslide-valve movements. Every hour during the trial the finished diagramis torn off the roll and a fresh one started, and when time is up theengine is stopped and the diagrams compared. Then commence thecalculations, which are gone through somewhat in this manner: the commonmultiplier is found by multiplying the area of the piston in inches bythe speed of the piston in feet per minute and the product divided by32, 000 (Watt's horse-power), then the effective mean pressure found onthe diagram is multiplied by the common multiplier, and the quotientwill be the _indicated_ horse-power of the engine. 46. _Question. _--How is the consumption of coals apportioned to thehorse-power of the engine at the finish of the trial? _Answer. _--The consumption of coals in pounds is divided by the productof the indicated horse-power and the time in hours. The quotient is thequantity consumed per horse-power per hour. 47. _Question. _--Would the quality of the coals used in the trial be ofthe same quality as will be used in the ordinary working of the boilerafter the trial is ended? _Answer. _--No; the coals which are used in the trial are generally thebest Welsh, not shovelled up indiscriminately, but carefullyhand-picked, weighed and wheeled into the stoke-hold; the engine duringthe trial is lavishly supplied with oils and tallow, with greatregularity. After the trial, and the horse-power is indicated, theboiler resumes her ordinary work; the stoker is ever after expected tocreate sufficient steam with very inferior coals to develop the sameamount of power in the engine as was done in the trial. I think that isvery unfair to the stoker. * * * * * "Let the finish give you pleasure" was the last headline in my lastschool copybook in the long, long ago; and it has given me as muchpleasure to begin this catechism as to finish it; it has given mepleasure to offer to brother stokers my very long experience in stoking, and kindred vocations, such as hydraulics, steam-pipe joint making, water-pipe joint making, engine driving, etc. , in the hope that in theperusal of this catechism they may find something to their advantage. And with my best wishes for their future success, remain their truefriend. W. J. C. 1906. * * * * * LONDON: PRINTED BY WILLIAM CLOWES AND SONS, LIMITED GREAT WINDMILL STREET, W. , AND DUKE STREET, STAMFORD STREET, S. E.