Etzler’ calculation on this head: To form a conception of the power which the tide affords, let us imagine a surface of 100 miles square, or 10,000 square miles, where the tide rises and sinks, on an average, 10 feet; how many men would it require to empty a basin of 10,000 square miles area, and 10 feet deep, filled with sea-water, in 6¼ hours and fill it again in the same time? As one man can raise 8 cubic feet of sea-water per minute, and in 6¼ hours 3,000, it would take 1,200,000,000 men, or as they could work only half the time, 2,400,000,000, to raise 3,000,000,000,000 cubic feet, or the whole quantity required in the given time.

This power may be applied in various ways. A large body, of the heaviest materials that will float, may first be raised by it, and being attached to the end of a balance reaching from the land, or from a stationary support fastened to the bottom, when the tide falls the whole weight will be brought to bear upon the end of the balance. Also, when the tide rises, it may be made to exert a nearly equal force in the opposite direction. It can be employed wherever a point d’appui can be obtained.

“However, the application of the tide being by establishments fixed on the ground, it is natural to begin with them near the shores in shallow water, and upon sands, which may be extended gradually further into the sea. The shores of the continent, islands, and sands, being generally surrounded by shallow water, not exceeding from 50 to 100 fathoms in depth, for 20, 50, or 100 miles and upward. The coasts of North America, with their extensive sand-banks, islands, and rocks, may easily afford, for this purpose, a ground about 3,000 miles long, and, on average, 100 miles broad, or 300,000 square miles, which, with a power of 240,000 men per square mile, as stated, at 10 feet tide, will be equal to 72,000 millions of men, or for every mile of coast, a power of 24,000,000 men.”

“Rafts, of any extent, fastened on the ground of the sea, along the shore, and stretching far into the sea, may be covered with fertile soil, bearing vegetables and trees, of every description, the finest gardens, equal to those the firm land may admit of, and buildings and machineries, which may operate, not only on the sea, where they are, but which also, by means of mechanical connections, may extend their operations for many miles into the continent. (Etzler’s Mechanical System, page 24.) Thus this power may cultivate the artificial soil for many miles upon the surface of the sea, near the shores, and, for several miles, the dry land, along the shore, in the most superior manner imaginable; it may build cities along the shore, consisting of the most magnificent palaces, every one surrounded by gardens and the most delightful sceneries; it may level the hills and unevennesses, or raise eminences for enjoying open prospect into the country and upon the sea; it may cover the barren shore with fertile soil, and beautify the same in various ways; it may clear the sea of shallows, and make easy the approach to the land, not merely of vessels, but of large floating islands, which may come from, and go to distant parts of the world, islands that have every commodity and security for their inhabitants which the firm land affords.