108 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



[March, 



mansliip. This cutter must be kept in its place by two cross cutters; and 

 these again, by a thong of leather, passed through some holes in them. 



12. It «ill seldom happen that the plug tree can be hung directly under 

 its arch ; you are to place them exactly in the places fixed by the drawings ; 

 that of the arch will always be found right in the geiicral section ; but the 

 place of the plug tree and guide posts must be taken, by measuring from the 

 nozzle, in the drawing of the working gear. A strong iron bracket with a 

 stay must be fastened to the top of the plug tree, in such a direction that 

 the point of the bracket may come directly under the arch. There must be a 

 hole in the point of the bracket, to receive the end of an iron rod, reaching 

 down from the chain ; and the end of this rod must be screwed, for five or 

 six inches, and have a nut on the lower side of the bracket, to adjust the 

 height of the plug tree by. 



13. There sliould be placed upon the spring beams, over the cylinder, two 

 uprights, connected at top by a strong cape piece. These uprights serve 

 to support a windlass, with a wheel and pinion ; by means of which, and a 

 pair of tackle pulley blocks hung to the cape piece, it will be easy to lift and 

 put the cylinder, Uc, in their places ; and after the engine is completed, it 

 makes it easy for the engine man to raise the cylinder lid, to pack the piston, 

 without ctfcer assistance 



The barrel of the windlass may be of oak, about six inches diameter ; and 

 must have a square gudgeon of iron driven quite through it ; on one end of 

 which, the toothed wheel must be fixed. The gudgeon may be from one and 

 a half, to two and a half inches square, according to the size of the engine ; 

 and the wheel about two feet diameter, driven by a pinion five inches diame- 

 ter ; but these may be larger, or less, according to the weights commonly to 

 be raised. It is necessary to mention to those who may look on a wheel and 

 pinion as a superfluous expense, that there is no trusting to windlasses 

 wrought by bars ; and that many bad accidents have happened through the 

 use of them, which obliges us absolutely to condemn them for this purpose. 



14. The springs to receive, and, in some degree, to save the blow when the 

 engine comes down too suddenly, are best made of a piece of a square dry 

 elastic timber, reaching from the plummer blocks, to nine or ten inches be- 

 yond the catch pins ; their size must be suited to that of the engine, from 

 six inches square, to twelve, or fourieen. The ends next the catch pins must 

 be sloped off on the under side, for four or six Icet in length, according to 

 the size of the engine ; so that their points may be one inch distant from the 

 spring beams, to which they must be bolted down, by a screw bolt at the end 

 of the sloped part, and another at the end next the plummer blocks. The 

 pait of these springs which are struck by the catch pins, should be covered 

 by a plate of iron, and that again by a piece of strong leather, to prevent 

 the clattering noise they might otherwise make. 



15. The utmost attention to dimensions must be observed, in constructing 

 the masonry of the building; particularly in regard to heights; mistakes in 

 tbem are productive of the worst consequences. 



16. The condenser cistern must be made of best Dantzic thiee inch deal 

 plank, if it can be got. If not readily to be got, any other good red deal, 

 or oak, may be employed ; but whatever kind of wood be used, be sure lo 

 cut off all the sap wood, otherwise the cistern will soon become useless. The 

 best way of putting the cistern together is, by means of long screw bolts ot 

 iron, about three-quarters square, put through the planks edgeways, from 

 top to bottom of the cistern. These screws may be eighteen inches distant 

 from one another. The bottom may be put together in the same manner with 

 screws ; and then fixed down upon the beam, or beams : and be supported by 

 so many more smaller beams, as may be necessary. If the cistern is not 

 more than seven feet long, no uprights, on the outside, are necessary ; only 

 one, about six inches square, in each corner, in the inside; and in no cistern 

 ought there to be any upriglits on the sides next llie wall. The joints of the 

 planks should be plain joints and put together on a strip ot coarse flannel, 

 soaked with a mixture of tar and tallow, eijual parts, and warm ; or upon 

 bullrushes. A large cock or a brass valve should be fixed in the boiloni ol 

 the cistern, to let oil' the water occationally ; and a notch, about four inches 

 deep, and eighteen inches broad, wiih a trough fitted to it, should be made 



^ in the upper edge of the cistern, to convey away the waste water. If surlace 

 1 water cai.not be found to supply the injection, a small pump should be fixed, 

 to bring up water from the main pump head inio this cistern. In case the 

 water from the pit is good, and is raised to the surface, the main yamp may 

 deliver it rlirectly into ihe cistern j but if the water le subject to be muddy, 

 or mixed with sand, &c. it will lie best to put it into another cistern, to de- 

 posit some part of the matter first. If the pit water be vitriolic, or encrusting 

 water, it becomes necessary to use every means to procure better water, other- 

 wise it will destroy the condenser, &c. 



17. In making the boiler, you should use rivets between five-eighths and 

 three-fourths inch diameter. In the bottom, and sides, the heads of the 

 rivets should be large, and placed next the fire, or on the outside ; and in the 

 boiler top, the heads should be placed on the inside. The rivets should be 

 placed at tuo inches distance from the centre of one rivet to the centre of 

 the other ; and their centres should be about one inch distant from the edge 



of the p'ale. The edges of the plate should be evenly cut to a line, both 

 outsiile and inside. It is impossible to make a boiler top truly tight, which 

 is done otherwise. After the boiler is all put together, the edges of the 

 plates should be thickened up ; and made close by a blunt chissel, about one 

 quarter inch thick in the edge, impelled by a hammer of three or more pounds 

 weight ; one man holding, and moving the chisel gradually, while the other 

 strikes. All the joints, above water, should be wetted with a solution of sal 

 ammoniac in water, or rather in urine ; which, by rusting them, will help to 

 make them steam t'ght. After the boiler is set, it may be dried by a small 

 fire under it ; and every joint and rivet above water, painted over with thin 

 putty, made with whiting and linseed oil, applied with a brush. A gentle 

 fire must be continued until the putty becomes quite hard, so as scarcely to 

 be capable of being scratched off by the thumb nail ; but care must be taken 

 not to bum the putty, nor to leave off, until it becomes dry. 



18. In building the brickwork of the boiler setting, no lime must be used 

 where the fire or flame comes ; but a mortar made of loam, and sand, and 

 clay ; but lime mortar should be used towards the outside. Pieces of old 

 cart tyer, or other such like pieces of iron, may be laid under the chime of 

 the boiler; between it and the bricks ; which will prevent its being so soon 

 burnt out there. The brickwork, which covers the boiler top, should be laid 

 in the best lime; which will not hurt it there, but will preserve it. The 

 mortar should be used thin ; and the boiler top well plaistered with it ; which 

 will conduce greatly to tightness, if done some time before the engine be set 

 to work. If your lime be not of the species which stands water, it will be 

 well to mix some Dutch, or Italian terraso, or pan scratch from the salt 

 works, with it; but in any case, the lime should be newly slacked. In car- 

 rying up the brickwork, ronnd the flues, long pieces of rolled iron should be 

 built in, in two or three courses, to prevent the brickwork from splitting- 

 Four holes, at convenient places, should be made into the flues, large enough 

 to admit a boy to go in, to clean them. One of them may be over the fire 

 door ; and another light behind the damper, in the backside of the chimney. 

 This last, may be as high as the flues themselves are. These holes, when 

 not in use, must be built up with nine inch brick work, and made perfectly 

 air tight. Immediately above the brick work of the boiler setting, a hole 

 must be left in the chimney, on the side next the boiler. This hole must be 

 as wide as the chimney ; and must have a sliding door fitted to it, to open it 

 more or less, at pleasure; the use of it is to moderate the draught of the 

 chimney, and to prevent the flame being drawn up it, before it has acted 

 sufficiently on the boiler. A groove must be left in the brickwork, for the 

 damper to move up and down m, easily ; which should fit flat to the face of 

 it. The damper may be made to move easily, up and down, by means of a 

 wheel, on a beam, with a counterpoise equal to the weight of the dam| er. 

 The best form of a fire door is two feet long, and one foot high, inside mea- 

 sure, to have leaves, made of boiler plates, hinged on the two sides, and 

 over lapping one another, about an inch in the middle. The scantling of the 

 frame may be three inches broad by two inches thick. 



19. The gauge pipes may be fised into the boiler top, in some conven'ent 

 place; the lower end ot the longest should reach within six inches of the 

 top of the flues ; and Ihe shortest should be four inches above it. The feed 

 pipe should reach two feet under the surface of the water in the boiler ; and 

 should have a valve, at its lower end, to prevent the water being ever forced 

 up through it, by the steam. Its upper end should lise seven feet higher 

 than the surface of the water in the boiler. It should be supplied with water 

 by a pipe from the top of the hot water pump, regulated by a cock near the 

 feed pipe. 



20. If you have not land water that will naturally run into the ci ndenser 

 cistern, you must make a pool somewhere in the neighbourhood to receive 

 the water from the hot water pump and reserve it for supplying the boiler 

 and condenser cistern when the engine siands still on any occasion. 



This pool must be at least forty feet long, and twenty feet wide, and to 

 ho d three feet deep of water; and pipes, or troughs, must be laid from its 

 bottom, to the boiler feed pipe and cistern. That, at the feed pipe, must 

 have a cock on purpose. It is meant, that the pool be simply dug in the 

 earth; and be lined «ith turf, puddled ; or otherwise made water tight. If 

 no ground, within a reasonable distance, be high enough for the water lo 

 run from the bottom of the pool into the boiler, then a pool may be made o 

 lower ground, and a hand pump be fixed up, to supply the boiler and cis- 

 tere ; but this ought to be avoided, if possible. 



This concludes the first part of Messrs. Boulton & Watt's instructions. 

 In our next JoHrH«/, we shall resume the subject, and give their '" Directions 

 Jor Putting the Engine together ;'^ and also an engraving of the description of 

 Kngine lelerred to in these particulars. 



Silver Mine. — We learn from Stockholm, that a silver mine, which is 

 expected to be very productive, has been discovered near the town of 

 Lindsherg. 



