Hydrostatics and pneumatics / [Dionysius Lardner].

  • Lardner, Dionysius, 1793-1859.
Date:
1831
Catalogue details

Licence: Public Domain Mark

Credit: Hydrostatics and pneumatics / [Dionysius Lardner]. Source: Wellcome Collection.

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    piston P be made to descend one inch, a quantity of water which occupies one inch of the cylinder C will be expelled from it; and as the vessel ABCD is filled in Fig. 6. D C every part, and its sides cannot yield, the piston P' must be forced up until room be obtained for the water which has been expelled from C. But as the cylinder C' is ten times larger than the cylinder C, the height through which the piston P' must be moved to obtain this room will be ten times less than that through which the piston P was caused to descend. Thus, while one pound on the piston P was moved through one inch, a weight of ten pounds on the piston P' has been moved through the tenth of an inch. By repeating this process ten times, we shall move ten pounds on the piston P' through a height of one inch, by ten distinct efforts, each of which moves one pound through one inch. The force expended, and the effect produced, is therefore the same as if the weight of ten pounds, with which the piston P' was loaded, were divided into ten equal parts, and these parts severally raised by ten distinct efforts through the height of an inch. The force, therefore, expended to produce a given effect is the same as if no machine was used.* (7.) It is not the least surprising circumstance in the