1844.] 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



lot 



General Directions for Building the Engine House, and Constructing some parts 

 of tlie Engine. 



1. Having fixed upon the proper situation of the pump in the pit, from its 

 centre, measure out the distance lo tlie centre of the cyhnders ; — that is, the 

 length of the working beam, or great lever, and the half breadth ofeacli of 

 thi.' great chains, ' tl-.en, from the centre of the cylinder, set off all the 

 other dimensions of the house, including the thickness of the walls. Dig out 

 the whole grounds included, to the depth of the bottom of the cellar ; so that 

 the bottom of the cylinder may stand on a level with the natural ground of 

 the place, or lower, if convenient. For the less height the house has above 

 ground, so much the firmer will it be. The foundation of the walls must be 

 laid at least two feet lower than the bottom of the cellar, unless the founda- 

 tion be firm rock ; and care must be taken to leave a small open drain into 

 the pit, quite through the lowest part of the foundation of the lever wall, to 

 let oft' any water that may be accidentally spilt in the engine house, or may 

 naturally come into the cellar. If the foundation, at that depth, does not 

 prove good, you must go down to a better, if in your reach ; or make it good 

 by a platform of wood, or piles, or both. 



2. The foundation of the lever wall must be carried down lower than the 

 bottom of the space left under the condenser cistern, to get at the screws 

 which fix the condenser ; and two short walls must be built to carry the 

 beams under the condenser cistern. Two other slight walls must be built, one 

 on each side, at a little distance from the cistern, to keep the earth from it, 

 which would otherwise cause it to rot. 



3. ^yIthin the house, low walls must be firmly built to carry the lower 

 cylinder beams, so as to leave sufficient room to get to the holding down 

 screws ; and the ends of these beams must also be lodged in the wall ; but 

 the platform must not be built on them, until the house is otherwise finished. 



4. The lever wall must be built in the firmest manner, and run solid, course 

 by course, with thin lime mortar; and care must be taken that the lime has 

 not been long slaked. If the house be built of stone, let the stones be long 

 and large, and let many headers be laid through the wall ; it should also be 

 a rule, that every stone be laid on the broadest bed it has, and never set on 

 its edge. 



A course, or two, above the lintel of the door which leads to the condenser, 

 build, in the wall, two parallel flat thin bars of iron, equally distant from 

 each other, and from the outside and inside of the wall, and reaching the 

 whole breadth ol the lever wall. About a foot higher in the wall, lay at 

 every four feet of the breadth of the front, other bars of the same kind, at 

 right angles to the former course, and reaching quite through the thickness 

 of the wall; and at each front corner lay along bar, in the middle of the 

 side walls, and reaching quite through the front wall. If these bars be 10 It. 

 or 12it. long, it will be sufficient. \V hen the house is built up nearly to the 

 bottom of the opening under the great beam, another double course of bars 

 must be built in, as has been directed. 



5. At the level of the upper cylinder beams, holes must be left in the walls 

 for their ends, with room to move them laterally, so tliat the cylinder 

 may be got in ; and smaller holes must be left quite through the walls for the 

 introduction of iron bars ; which being firmly fastened to the cylinder beams 

 at one end, and screwed at the other, or outer end, will serve, by their going 

 through both the front and back walls, to bind the house more firmly to- 

 gether. 



6. The spring beams, or iron bars fastened firmly to them, must reach quite 

 through the back wall, and be keyed, or screwed up tight ; and they must be 

 firmly fastened to the lever wall on each side, either by iron bars, firm pieces 

 of wood, or long strong stones reaching far back into the wall. They must 

 also be bedded solidly ; and the sides of the opening built in the firmest man- 

 ner with wood or stone. The spring beam must always be laid eight inches, 

 on each side, distant from the working beam, to give room for the side 

 arches 



7. The house being finished, a wooden platform, of two and a half inch 

 plank, must be laid on the lower cylinder beams; and the centre of the 

 cylinder being accurately marked on it, four hules must be bored through the 

 cylinder beams for the holding down screws; and four boxes, about SL'Ven or 

 eiglit inches square, and as long as the stone platform uill be deep, must be 

 placed perpendictdarly over them. Then the stone or brick platform must be 

 built up to the level of the cylinder's bottom. It must be composed of the 

 heaviest materials which can readily and cheaply be procured. A very solid 

 pillar of stone or brickwork, laid in the best lime mortar, must be carried up 

 directly under the cylinder, and must be, at least, of the diameter of the out- 

 side of the flanches ; the rest of the platform may be filled up with heavy 

 materials, bedded solidly in a mortar of clay and sand, and well beat into 

 their places, so that they may never settle or yield. 



1 [N.B. — It may be necessary here lo state, that as the instructions here given were 

 for the first engines made and erected under the patent, they were applied to pumping 

 only; that the engines were of the fiind denominated **aljnu8pheric," and that, as the 

 parallel motion was not ttien invented, tlie circular motion ot dilieient pails ot the beam 

 were changed into the approximatively vertical, upward and downward, motion of the 

 piston rod, and pump rods, by arch heads, or " arches," on the beams ; and by suspending 

 tlie rods to them by chains.] 



8. The lever, or great working beam, is best when composed of one single 

 log of seasoned oak , where that cannot be obtained, two maybe used, or 

 four, or more. The fewer logs it is composed of, so much the more durable 

 will the lever be, or of so much smaller scantling may it be made. This beam 

 must be fashioned and mounted. The diagonal stays, fastened to the arches, 

 and on the lower log, or lower edge of the beam, will prevent the logs from 

 sliding on one another, by the difference of the direction in which the chains 

 act upon them, when the end of the lever is up or down. These stays must 

 be let into the side of the beam, that the other diagonal braces may pass over 

 them. The diagonal braces, which reach from the top of the king posis to 

 the lower edge of the beam, are intended to prevent the logs from bending or 

 sliding on one another. They are fastened to the beam, at their lower end, 

 by means of a strong square bar of iron screwed at both ends, which passes 

 through the beam, and serves to bind it together, laterally. They must no- 

 where else have any fixture to the beam. Their screws, at the top of the 

 king posts, must be tightened from time to time, as required. 



The gudgeon must be placed on the top of the beam, and must not be at 

 all let into it ; only the corners of the log may be taken off, to fit the saddle 

 plate, and to prevent the saddle plate from sliding on the beam. One or two 

 pieces of hardwood, about five inches broad, and a foot long, by three inches 

 thick, miy be let into the upper side of the beam, one inch deep, with their 

 ends butting up against the saddle plate. They must be spiked down in 

 their places ; and both them, and the saddle plate, must be laid in a bed of 

 tar and tallow, mixed and used boiling hot, which will prevent the wood 

 rotting under them. A clamp of oak, four inches thick, and from four to 

 six feet long, must be spiked on the lower side of the beam. This clamp 

 must be rounded on the edges ; its use is to prevent the beam straps from 

 hurting or weakening the beam in that critical place. These beam straps 

 must not be made out of thick bars, or lumps of iron ; but must be made up 

 by a number of thin or small bars welded together ; and they, and all the 

 other iron work of the beam, must be made of iron of the best quality. All 

 the big pieces should be made up of smaller, or thin bars, in the way I have 

 mentioned. Upon no account, whatever, let any holes be bored through the 

 beam near the gudgeon, nor any thing else be done, which may weaken it 

 there. 



9. The arches for the plug tree and condenser pumps should be screwed to 

 the beam by screw bolts, nhich should pass through the joints of the logs of 

 the beam, if it be composed of more logs than one, and one bolt may gene- 

 rally pass above the beam ; these bolts also serve to keep the beam together 

 laterally ; these arches should be maile with a shotdder of two inches pro- 

 jection to rest on the upper side of the beam. The tails of the mattingales 

 of the plug tree, and the condenser pumps, must also be secured by bolts 

 passing through the beam in some joint, if it can conveniently be done. The 

 lower end of the king post should have a hollow in it, to fit the gudgeon on ; 

 but care should to be taken that it rests upon the gudgeon, and not uj/on the 

 saddle plate. It should be contrived, that the tails of two of the great mar- 

 tingales should rest on the middle of each of the two logs which compose 

 the thickness of the beam ; that is, when the beam consists of lour or more 

 logs. The martingale screws should be strong, and should go quite down 

 through the beam, as it is them that principally keep the beam together in 

 the direction of its depth. Near these screws must be placed the keys, or 

 pieces of hard dry wood ; which, being half let into each log of the ber.m, 

 prevent the logs from sliding one upon the other. These keys should never 

 be above two inches thick ; lb U is, one inch let into each log : they may be 

 made in three ]>ieces, the two outside pieces dovetail ways, and the middle 

 one tapering ; by driving up which, they are made to join themselves in their 

 mortoises. Or they may be made of one piece, six inches broad at one end, 

 and five at the other, so that by driving the whole in, it may check the 

 sliding of the logs. If there are more sets of logs than two in the depth, 

 the keys must be placed, alternately, on different sides of the martingale 

 screws. Care must be taken, in placing the chains for the plug tree and con- 

 denser pumps, that all the heads of the chain bolts be next the beam, and 

 that they be far enough off' not to rub on the diagonal stays, or any other 

 thing. 



10. The great chains must be made of the very best iron, and the martin- 

 gales must be placed so, that the adjusting screws may lie parallel to the 

 arches, and the upper surface of the head of the martingale be at right an- 

 gles to them. The holes, in the martingales, should be quite easy for the 

 adjusting screws ; and a washer, thinned about the outer edges, should be 

 quite easy for the adjusting screws ; and a washer, thinned about the outer 

 edges, should be put under the nuts. There should be a sufficient length of 

 chain, to reach one link lower than'the under end of the arch of the beam. 



11. The cap and cross-bar, for the piston-rod, should be firm work, of 

 good iron. The mortoise, in the cap, should be made exactly to suit the 

 mortoise in the piston-rod ; and the cutter, or forelock, to fit them both 

 exactly ; and the cutter above all things should be the very best of iron, as 

 the whole depends on it. There is always a sufficient size given it in the 

 drawings ; so that, if it should iaii, it must be the fault of the iron, ot work- 



