BEER pump. The plate explains the construction of a set of beer pumps, as made by Mr. Thomas llowntree, engine maker, Blackfriars road: the pumps are not of the common construction, but similar to that made use ofin his extinguishing en gine : they are double, and throw out the liquor at either motion ofthe handle. Fi gures 4 and 5 are two sections of a pump at right angles to each other : fig. 4 being a section through the dotted line A B, fig. 5 : and fig. 5 a section through C ll, fig. 4: the same letters are used in both fi gures EE:FF is a brass cylinder with a flanch, E E (dotted in fig. 5) in front : G G, fig. 4, is a cover screwed to the cy linder with a stuffing box 71, in the centre, to receive the spindle H : 1 is a partition in the cylinder, with a packing at a, to embrace thespindle, and make a tight joint, this has two valves, b, d, shutting downwards upon holes made in the parti tion : K is the suction pipe, bringing li quor to the lower division of the cylinder, but has no other communication with the upper, but the two valves, b, d: Lis the piston fixed to the spindle, and fitting the cylinder tight all round, so as to divide the upper part into two other parts : e,f, are copper pipes, to convey the liquor from the upper half of the cylinder to a cham ber N, and its return is prevented by valves g, h, on the ends of the pipes : 0 is the forcing pipe screwed to the chamber N ; when the piston is moved by the han dles on the end of its spindle towards b; for instance, the valve b will be shut, and the liquor on that side, finding no other pas sage, passes through the pipe e and valve g, and into the chamber N, and is con veyed by means of the force pipe 0, where required: the same motion of the piston, enlarging the space on the side it, shuts the valve h at the end of the pipe f, and formed a vacuum : the pressure of the atmosphere upon the surface of the liquor, in which the end ofK is immersed, forces it through the pipes, opens the valve d, and restoresthe equilibrium. The operation is exactly the same when the piston is moved in the other direction from L to d: the liquor going to 0 through f and coming from K through b. Three these pumps are mounted in a frame, as shown in figures 1 and 2, which is inclosed in a box, with a circular top A B, and the handles a, b, c, project through it : the suc tion-pipes d, e, f, go through the floor in. to the cellar below : the force-pipes from the top of 'he pumps are bent, and come through the side of the box where the pots are held to be filled : his a small cis tern to receive the waste, which is con veyed by a pipe to a waste butt in the cel lar: the suction-pipes pass through the floor, and are carried along the ceiling un til just over the butt ; they are then bent down, and jointed to the cock drove into the butt in the usual manner : the pipes are of lead, half an inch bore, and very thin, so that they can be bent (without breaking) to reach any particular place ; they are connected with the cock by a screw joint, shown in fig. 3 : A B is the
brass cock ; its outer end B cut into screw, and the bore enlarged to form a socket for a short brass pipe D, soldered to the leaden one : a piece ofleather putbeween the end of the cock and the shoulder of D makes a tight joint ; these are kept toge ther by a collar E, embracing the should er of D, and screwing upon the end of the cock: e is a stub projecting from it, by which it is turned. The piston of the pump consists of three plates, figures 4 and 5 : the middle one (which should be called the piston) is cast in a piece with the spindle, and fits the cylinder as true as possible without touching ; then square pieces of leather are put on each side of the piston, to form the joint, and a thin plate of metal put on over the leath ers, and screwed to the piston, (as shown at L, fig. 4,) holds it all fast. The body of the piston, as we have said befbre, fits the cylinder as close as possible: the leath ers are about half an inch bigger all round, so that, when they are put into i I I the cylinder, their edges will turn up all round, and form a dish ; and its elasticity, pressing. against the cylinder, prevents any of the liquor getting through ; the two outside plates must be the thickness of the leather less all round than the cy linder, and their use is, to keep the edges . of the leather up against the cylinder, and to hold the four screws by which the leather is fastened. The back of the spin dla opposite the piston must have a pack ing of hemp drove into the space a behind it, to make all tight, and the metal edges of the partition, I, should fit it as closely as possible to work free : the valves are pieces of leather fastened at one side of the hole, and a piece of brass is rivetted to. them, to make them heavy enough to fall, and prevent the leather bending by the pressure of the column of liquor : the top of the cylinder at N is filed flat, and the chamber which is a square prism,placed on it with leather between, and the lid is put on the upper part, and all screw ed together by four long screws, going through the lid, and the corners of the chamber, and tapped into the cy linder below. When these valves want repairing, the four screws are taken out, and the lid can then be removed. To come at the valves b, d, the cylinder lid G can be removed, by taking out five screws ; the lid has a hole turned in its centre, which fits the spindle II as close as possible : the hole afterwards enlar ges, and has a piece of leather (repre sented by the dark part, fig. 4,) bent into a cup, so as to embrace the spindle : the leather is kept in its place by a perforated screw n, tapped into a pro jecting part of the lid, and pressing on the leather ; the suction-pipe K of the pump is joined to the leaden pipes by a screw joint K, so that it can be separated, occasionally to remove the pump from the frame.