All that is known concerning his efforts is sufficiently illustrated by the following cuts and language from Dircks:
Fig. 1 may be taken as a scheme belonging to the fifteenth century. It seems to be placed at the head as a simple or elementary design for future improvement. It is a chambered drum wheel, containing balls or weights, which, being always farthest from the center on one side, as compared to the other, are expected to keep the wheel constantly rotating.
Fig. 2. Failing in this scheme, the inventor next offers one with weighted levers, which are to fall outwards on one side, but to fall inwards on the opposite side, the weight at the same time sliding up the lever when vertical at the bottom, so as to be nearer the center throughout on the ascending side. But how the weight is to be made to ascend at the bottom remains to be shown.
Fig. 3. The difficulty of elevating the weight would appear to have suggested its immersion in a trough of water, as here shown. The weights seem to be attached to some contrivance to float them upwards; but we are perplexed, and so no doubt was da Vinci, how to sink them, or being sunk, how to render them again buoyant by any self-motive process.
Fig. 4. It would appear as though the difficulties observable in Fig. 3 were attempted to be met here, in a plan which evidently combines several views of the case, yet without removing the main difficulty; for although the weight at the end of the long arm may be quite capable of sinking in the liquid, we still inquire, How is it ever to be raised again?
Fig. 5 seems to be an incomplete sketch, and a mere variation on the preceding designs, with the addition either of machinery below to be worked by it, or to give it motion. Possibly it was proposed to have a magnet at the bottom of the vessel.
Fig. 6 appears to be two designs in one sketch. On one side we have long single levers, with a single weight at their ends, and a weight between each at the periphery; on the other end, double or forked levers and double weights. Its mixed character renders it probable that it was merely some preliminary sketch.
The great value of the present exhibition of these early contrivances of misdirected mechanical ingenuity consists in the convincing evidence which they afford, that all young inventors who occupy themselves in the search for self-motive machines, do little more than reproduce the blunders of a past age. After a lapse of five centuries modern inventors often become patentees of contrivances which are only more complicated than the assumed-to-be overweight wheel of Wilars de Honecort, or the six similar ones of Leonardo da Vinci. But such has hitherto been the ignorance of mechanics on this subject, that Fig. 1 of the annexed diagrams has frequently been adduced by writers on the subject, as the veritable wheel invented by the Marquis of Worcester, in the seventeenth century!
A. Capra's Device
In 1678, A Capra, of Italy, revived the ancient, but still favorite scheme that dates back to the 13th century. (See page 22 ante.) He illustrates his idea with the following figure and the following comment:
On the wheel A (of the facsimile engraving opposite), which must be hung well equipoised between two uprights, are appended counter-weights, eighteen in number, all precisely at the same distance from each other, and all exactly of the same weight. The counter-weights are provided with a small ring by which they are hung.
Whilst the counter-weights B are farther from the center C of the wheel, they weigh more than the counter-weights I, because these are low and nearer to the center C of the wheel, so that the counter-weights B descend and the weight I drops; and whilst the weight B is alternately descending and the weight I ascending, the wheel will revolve continually. But it must be understood that it is necessary to make the wheel perfectly true in equilibrium, so that it do not weigh more on one side than on the other on account of the counter-weights.
The Device of Dixon Vallance. England, 1825
This inventor was certain he had overtaken and captured the ever-illusive Perpetual Motion. He gives a description of his happiness and his machine in the following effusively joyous language:
The annexed drawing shows how I have at length taken this enticing jilt (perpetual motion), though after a long and weary chase—
Through pleasant and delightful fields,
Through barren tracts and lonely wilds;
'Mongst quagmires, mosses, muirs and marshes,
Where deil or spunkie never scarce is!
By chance I happened on her den,
And took her when she didna ken.
W W W W represents a wheel with twelve hollow spokes, in each of which there is a rolling weight or ball. C C C C is a chain passing over two pulleys P P. There is an opening round the wheel from the nave to the circumference, so as to allow the chain to pass freely and to meet the weights. The weights are met by the chain as the wheel revolves, and are raised from the circumference till they are at last brought close to the nave, where they remain till, by the revolution of the wheel, they are allowed to roll out to the circumference. By this arrangement the weights are, on one side of the wheel, always at the circumference, so that that side is more powerful than the other, which causes the wheel continually to revolve. F F F F is the frame of the machine; M M M M the mortices for joining the two sides of the frame by cross rails. The arrows point out the direction in which the wheel turns.—I am, yours, &c., Dixon Vallance. Liberton, Lanarkshire, Nov. 10, 1825.
