Another class of devices for getting work out of a machine which has never been fed into it may be illustrated by what we may term the "Grindstone" paradox. Its supposed action is due to the well-known fact that articles when immersed in a liquid tend to float. Take a block of wood the shape of a grindstone and immerse one half of its mass in a vertical tank of water. The flotative power of the water will cause this half to rise continually, and to consequently keep the block constantly turning round its axle. We leave the explanation of this paradox to the reader. Sufficient is it to say here that, alas! brutal experiment proves it will not work.
CONCERTINA MACHINE.
Closely allied to the "Grindstone" paradox is the "Concertina" machine, where a series of weighted concertina-like chambers attached to a band passing round pulleys collapse when descending into a tank of water, but expand, and therefore become lighter, when the other side of the band is reached. The expanded chambers on the left of the picture act like a series of corks, while on the right the closed chambers act as dead weights. By this means it was anticipated continuous rotary movement would be obtained.
WATER MOTOR CAR.
Another favourite scheme is to employ the well-known property of liquids to rise of their own accord against the force of gravity when in microscopic channels, such as are found in all porous bodies, this property of rising being due to what is known as "capillary attraction." For instance, it is a matter of everyday observation that oil ascends a wick, water passes up over the edge of a basin through a towel which, partially immersed in the water, hangs over the side. Some idea of the enormous power of this property of ascending is given by a celebrated French savant who has found that capillary action is capable, under favourable circumstances, of exerting a pressure four or five times as great as that of the atmosphere, and who thinks this is largely efficient in promoting the ascent of sap in plants. Consequently, if this natural uprising property of liquids could be only laid hold of, the problem of getting work for nothing, so thinks our schemer, would thereby be solved. We have selected for illustration a form of apparatus where, on the left, a bundle of flexible sheets is placed almost in contact, so that the liquid into which they are dipped rises in the microscopic spaces between them. This provides a "head" of water, which is expected to overbalance the right hand of the system, where the sheets have been separated by the wires of a grid, or other equivalent, so as to destroy the capillary action on that side.
A CAPILLARY MOTOR.