A Panemore, or globular wind-mill, erected in the centre of a ship, has been proposed for the turning of two wheels or paddles, placed on the bows, which would thus impel the vessel forward in any required direction. The panemore, which was invented by M. Desquinemare, consists of a kind of globe placed on the top of a mast, on which it always turns round with the wind. In consequence of the ingenious adjustment of the curves which it presents in all its points, the rotary motion is always in the same direction, be that of the wind as it may; and their utmost violence, instead of being detrimental to its action, only augments its power. The means of the instrument increasing in a cubical ratio when the wind doubles its velocity; and by doubling the surface its power is increased eight-fold.
No. XVI.
How to make a sea-castle, or fortification, cannon-proof, capable of a thousand men, yet sailable at pleasure to defend a passage, or, in an hour's time, to divide itself into three ships, as fit and trimmed to sail as before; and even whilst it is a fort or castle, they shall be unanimously steered, and effectually be driven by an indifferent strong wind.
NOTE.
Scheffer, in his treatise entitled De Militiâ Navali, describes a vessel of a somewhat similar construction: it was composed of four floating tanks, or parts of vessels, which could at pleasure be joined together by means of bolts. Bomb-proof batteries of prodigious force were used by the Spaniards in their attack on Gibraltar, in 1782. Their upper decks were at an angle of about forty-five degrees, and composed of successive layers of oak-planking and raw hides. These offered an irresistible barrier to the shot and shells commonly used, till General Elliot decided on the application of red-hot balls, which, by burning a passage through the outer layers, quickly communicated to that part of the hold used as a depository for powder, &c., and the consequence was, the entire destruction of this immense flotilla.
No. XVII.
How to make upon the Thames a floating garden of pleasure, with trees, flowers, banqueting-houses, and fountains, stews for all kind of fishes, a reserve for snow to keep wine in, delicate bathing places, and the like; with music made by mills; and all in the midst of the stream, where it is most rapid.
NOTE.
The most celebrated gardens of this description were those made by the Mexicans on the great lake which surrounds the capital; here they planted trees, and cultivated maize, pepper, and other plants necessary for their support. In progress of time, as these floating fields grew numerous from the industry of the people, they formed among them gardens for flowers and other odoriferous plants, which were employed in the worship of their gods, and which served also for the recreation of the nobles. Every day of the year, at sun-rise, innumerable vessels, laden with various kinds of flowers and herbs, cultivated on the water, arrived by the canal, at the great market-place of the capital.
To form their floats, they first plait or twist willows, with roots of marsh plants, and upon this foundation they place the mud and dirt which they draw from the bed of the lake. When the owner of a garden wishes to change his situation, to remove from a disagreeable neighbour, or to come nearer his own family, he gets into his little vessel and tows the plantation after him.—Vide Nov. His. de Mexico par le Abbé Francesco Saverio Clavigero.
The floating pleasure bath moored in the River Thames, near Westminster Bridge, is supported by empty casks; and this plan, if assisted by mooring-chains, may be applied to gardens of any reasonable extent, even in the broadest and most rapid rivers.