242 



BENJ. PIKE S, JR., DESCRIPTIVE CATALOGUE. 



ing poured into the machine before using, and a rapid mo- 

 tion being given to it by a handle at top, the water in the 

 arms acquires a centrifugal force, opens the valves at the 

 end, and flies out into a circular trough prepared for it. 

 This machine is simple, but not so effective, as a well-made 

 pump. Price, $10.00. 



Brahma's Hydraulic 

 Press. (Fig. 264.) This 

 is a valuable instrument, 

 and one by which a pro- 

 digious power is obtained 

 with the greatest ease, 

 and in a very small com- 

 pass. The size of the 

 model represented is usu- 

 ally about twelve to four- 

 teen inches square, with a 

 cylinder about four inches 

 diameter. 



Its action depends upon 

 the principle that fluids 

 transmit pressure equally 

 in all directions. A solid 

 piston, E, is constructed 

 so as to move water-tight 

 in a cylinder. The space 

 beneath the piston is filled 

 with water, and communi- 

 cates by a small pipe with a forcing pump, worked by the 

 piston, B, by means of the lever, A, and by which the water, 

 which is contained in the cistern, G, is forced through the 

 valve, D, into the large cylinder. The large piston being 

 thereby driven up, carries with it the bed, H, and presses 

 closely together whatever may be above it. Whatever pres- 

 sure is exerted upon B, is transferred to E, and is increased 

 according to the relative size of the two pistons. Suppose, 

 for example, the piston at B to have a superficial area of one 

 inch, and the large cylinder of ten inches, then every ten 

 pounds pressure put upon B, will be increased by E ten-fold, 

 and become one hundred pounds; and as a person may 

 exert a force of fifty pounds on the lever, this weight alone 

 will give a pressure of 100X50 pounds, or more than 2 tons, 



