126 WELLS'S NATURAL PHILOSOPHY. 



What Is the Hy. ^^^ effectfl of the practical application of this principle are 

 drostatic Para- go remarkable that it has been called the Hydrostatic Para- 

 dox, since the weight, or force, of one pound, applied through 

 the medium of an extended surface of some liquid, may be made to produce 

 a pressure of hundreds, or even thousands of pounds. Thus, in Fig. 105, A 

 Fig 105 ^^^ ^ ''^^ *^*^ cylinders containing water connected 



by a pipe, each fitted with a piston in such a way as 

 rjT to render the whole a close vessel. Suppose the 

 T Ij'g area of the base of the piston, p, to be one square 

 1^ inch, and the area of the base of the piston, P, to be 

 1,000 square inches. Now any pressure applied to 

 the small piston will be transmitted by the water to 

 the large piston ; so that every portion of surface in 

 the large piston will be pressed upward with the 

 flame force that an equal portion of the surface in the small piston is pressed 

 downward. A pressure, therefore, of 1 pound acting on the base of the pis- 

 ton^, will exert an outward pressure of 1,000 pounds acting on the base of 

 the piston P ; so that a weight of 1 pormd resting upon the piston p, would 

 support a weight of 1,000 pounds resting upon the piston P. 



The action of the forces here supposed differs in nothing 



How do the fj-gni that of like forces acting on a lever having unequal 

 forces ^ctinsr t-j ^ 



in the Hydro- arms in the proportion of 1 to 1,000. A weight of 1 pound 



static Paradox acting on the longer arm of such a lever, would support, or 

 compare with ° ^ , . , , 



the forces act- raise a weight of 1,000 pounds actmg on the shorter arm. 

 ingontheariM t^^iq liquid contained in the vessel, in the present case, acts 

 as the lever, and the inner surface of the vessel containing 

 it acts as the fulcrum. If the piston p descends one inch, a quantity of 

 water which occupies one inch of the cylinder a will be expelled from it, and 

 as the vessel A a is filled in every part, the piston P must be forced upward 

 until space is obtained for the water which has been expelled from the cylin- 

 der a. But as the sectional area of A is 1,000 times greater than that of a, 

 the height through which the piston P must be raised to give this space, will 

 be 1,000 times luss than that through which the piston p has descended. 

 Therefore, while the weight of 1 pound on p has moved through 1 inch, the 

 weight of 1,000 pounds on P will be raised through only 1-1, 000th part of an 

 inch. If this process were repeated a thousand times the weight of 1,000 

 pounds on P would be rais'jd through 1 inch ; but in accomphshing this, the 

 weight of 1 pound acting on P would be moved successively through 1,000 

 inches. The mechanical action, therefore, of the power in this case, is ex» 

 pressed by the force of 1 pound acting successively through 1,000 inches, 

 while the mechanical effect produced upon the resistance is expressed by 1,000 

 pounds raised through 1 inch. 



„^ , . „ 292. The Hydraulic, or Hydrostatic 



What IB a Hy- ' 



drauiic Press? Press, Is a macliine arranged in such a man- 

 ner, that the advantages derived from the principle that 



