I do not suppose it will rise to the height of the cistern as I have figured it; but it may still be a question whether it may not be accomplished by a series of short tubes, the bottom of the one being placed in the cistern into which the next below discharges its water, each being constructed with a blast and two valves, in the same manner as the single tube--namely, the valves _x_ (under water) and _y_, worked in such a manner by the arms K L, that the one may shut when the other opens. Presuming that the water will rise to the top of the tube when the blast is in action (_x_ open and _y_ shut), the water in the part of the tube between the blast and _y_ will be discharged into the cistern at the next motion of the valves--namely, when _x_ is shut and _y_ opened, the blast, at the same time, being discontinued. Device by Means of Buoyancy Through Media of Different Densities An account of this appeared in "Mechanics' Magazine," 1825. The author apparently had no great faith in the accomplishment of Perpetual Motion, and yet it is manifest that he had not abandoned hope of accomplishing it, and is still thinking along some line of attaining it. It goes without saying that the device failed. The account furnished, however, is as follows: The unsuccessful (but far from fruitless) search made to discover the "philosopher's stone," and the "elixir vitæ," were productive of most important and beneficial results in the kingdom of chemistry; so, by a parity of consequence, I am disposed to believe that from inquiry after the "perpetual motion" (though equally unsuccessful), a similar good will result to the mechanical world. * * I beg leave to offer the prefixed device. The point at which, like all the rest, it fails, I confess I did not (as I do now) plainly perceive at once, although it is certainly very obvious. The original idea was this--to enable a body which would float in a heavy medium and sink in a lighter one, to pass successively through the one to the other, the continuation of which would be the end in view. To say that valves cannot be made to act as proposed will not be to show the _rationale_ (if I may so say) upon which the idea is fallacious. The figure is supposed to be tubular, and made of glass, for the purpose of seeing the action of the balls inside, which float or fall as they travel from air through water and from water through air. The foot is supposed to be placed in water, but it would answer the same purpose if the bottom were closed. [Illustration]