30 ANNUAL OF SCIENTIFIC DISCOVERY. 



of a governing valve, and also serves to protect a valve-rod, connecting 

 the operator on the platform with a small screw-valve in the bottom 

 of the float-case, designed for the ingress and egress of water. The 

 large hollow pipe is also provided with a small valve above, for gov- 

 erning the outlet of air. An induction-pipe enters at the top of the 

 well, and is always open. A discharge-pipe at the bottom is provided 

 with a valve, opening outward, whose lever is weighted, so as to 

 counterbalance the pressure of \vater tending to open it. The opera- 

 tion of the machine is as follows : Suppose the float-case full of air, 

 and at the bottom of the well, which is empty ; all the valves are shut. 

 If, then, water be allowed to fill the well, the buoyancy of the float 

 causes it to ascend, carrying upon its platform the goods to be ele- 

 vated. To descend, open the screw-valve in the float-case, and its gov- 

 erning air-valve, until a sufficient body of water has entered to destroy 

 buoyancy, when, the air-valve to the large pipe being also open, the 

 machine will descend with any desired velocity. On approaching 

 the bottom, the open screw-valve comes in contact with the weighted 

 lever governing the discharge, and has just time to open it, when the 

 float subsides into the bottom of the well, made of exactly the same 

 shape as that of the float, thus opening a passage between the float- 

 case and the discharge-pipe, permitting water to escape until its buoy- 

 ancy is sufficiently restored for a reascent. As the float-case exactly 

 fits in the bottom of the well (the fit being secured by packing) , no 

 water is permitted to escape from the well itself. It will thus be seen 

 that this machine possesses two advantages over the usual plans of 

 flotation. 1. Only the exact amount of water required to balance the 

 load and to overcome friction is expended for each lift. 2. The well 

 being always full, no time is lost in filling and emptying it. Journal 

 of Franklin Institute, July. 



IMPROVED HYDRAULIC RAM. 



THE Journal of the Franklin Institute for November contains the 

 report of a committee appointed to examine an improved hydraulic 

 ram, the invention of Mr. II. P. M. Birkinbine, of Philadelphia. The 

 principal improvements consist in constructing the discharge-valve so 

 that, as it rises into its seat, a portion of water is caught between the 

 valve and seat, and thus a water-cushion is formed, which prevents 

 the heavy blow, and the consequent rapid destruction of the apparatus. 

 The cup or air-chamber, which in all these machines is placed at the 

 discharging orifice, to arrest gradually the impact of the water there, 

 is placed upon the valve itself, and not upon the valve-seat, so that 

 the shock upon the valve is materially lessened. The drop-cup, into 

 which the guide-stem of the valve falls, is adjusted by means of a 

 wedge, controlled by an adjusting screw, so that the amount of fall of 

 the valve may be accurately set and altered when a change of circum- 

 stances requires it, so that the quantity of water discharged by the 

 valve can be reduced or increased at pleasure. The driving-pipe, or 

 that which conveys the water from the fountain-head to the ram, is in 

 a cycloidal form. About 1,000 of these rams, which the committee 



