The particular sympathetic acids and their proportions having been ascertained, the attracting-machine is prepared and charged with a large quantity of the sympathetic compound, sufficiently powerful to attract the person selected, although placed at some distance. To be effective, however, the operation must take place while the sun is shining; and it is also necessary that the person directing the machine should exercise a certain amount of will tending towards the end desired. The power of will is great, and there are a few persons who can make others do certain things without the aid of the instrument, by the power of will alone; but, in such cases, the person "willing" must be near the person acted on. XLIII. SHIPS. "Would ye triumph over the seas in all their fury? Would ye spare the lives of those who toil for you? Let your ships he harder than the rocks, swifter than the message-bird, more buoyant than the swan, and as enduring as the Mestua Mountain." Our ships are of peculiar form and construction, and of all but exhaustless strength and durability. In ancient times the form of a fish had been taken as a model for their construction, and the same form was continued for centuries. The ships built on this principle, however, often foundered at sea, or were broken to pieces, when driven against the rocks, by the violence of tempests. Moved by the loss of life and consequent suffering thus occasioned, I sought to construct a vessel that could neither founder nor be broken, at whatever speed it might move. I reasoned that a fish, formed to live and to act principally under the water, was hardly a fit model for ships intended to float on its surface, and certainly not to sink. After much consideration on the part of our scientific men, the form of the swan was successfully adopted as best fitted for sea-going ships. Our "Swan-ships," as I may call them, are constructed of timbers, previously seasoned to prevent insect breeding and to resist all tendency to shrink, and are completely covered with the hide of the hippopotamus, which, it should be observed, is impervious to water, and, when prepared for use, is so tough that no knife or machine, however sharp or powerful, can cut, pierce, or indeed make any impression upon it, until it has passed through a process, in which fire has a great part, and is thus purposely deprived of its impenetrable nature. In the construction of the ship, the outline of the swan is followed as nearly as possible. The prow rises out of the water, shaped like the bird's neck and head; the keel is rounded like the belly; the stern is an imitation of the tail; the legs are supplied by two large adjuncts in the shape of webbed feet, with the addition, however, of numerous wheels fastened round the swan's belly, which are partially immersed in the water and moved by powerful machinery within the vessel.