Page:Willich, A. F. M. - The Domestic Encyclopædia (Vol. 1, 1802).djvu/331

BOA water-tight, or filled with cork, or other light materials that will repel the water : the spaces between the timbers may iiilike manner be rilled np. By this means, the boat or "vessel will be so much lighter than the body of water it must displace in sinking, that it will v. ith safety carry more than its common bur- then, though the remaining space should by any accident be filled with water. Under the bottom, along the centre of the keel, is af- fixed a false one of cast iron, or other metal ; this will s-trengthen and protect the bottom from in- jury in many cases ; and, by being placed so much below the surface of the water, will act as ballast with more power than a much greater weight in the common si- tuation, and is much more safe, by being fixed in the proper place, and not liable to shift by any sudden motion of the boat or vessel. ICE-BOATS, a modern in- vention of Thomas Ritzler, of Hamburgh, whose name deserves to be transmitted to posterity ; as his ingenious and useful contri- vance has already saved many va- luable lives from a watery grave. We have given an accurate repre- sentation of such a boat, with our First Number, and shall here fur- nish the reader with the description. Fig. 1, Is a perspective view of the boat, the body of which con- sists of wicker-work covered with leather, to render it impermeable by water; and so remarkably light, that it may be easily ma- naged by one person, both on the ice and in the water. Its length, when measured on the outside, is "i feet in the keel, and 12 feet above from end to end : its breadth, 3 feet at the bottom, and 4 at the upper part. BOA [299 Fig. 2, Represents the plan of the boat, the bottom of which is shod with two small pieces of iron, marked 00, x : by means of two hooks, one of which is delineated on the plate, the boat may with the greatest facility be slided over the ice. In, the lower part, or bodv, of the vessel, there is a large opening, 3 feet long, and 15 inches wide, pointed out by o,v,% n>. 2 ; and o, fig. 3 ; the four sides of which are secured by a frame- work, marked r, fig. 1, and 3, to prevent the water from en- tering the vessel. Through this opening, also, the boatman is ena- bled to step iipon the ice in those places where it is too uneven to admit the sliding of the boat, and to carry it, by means of the han- dles, as represented in fig. 1, where the person standing, is marked only with dotted lines, to shew that he has quitted his former station in the boat. Ano- ther advantage derived from this aperture, in the middle of the boat, is the counterpoise which a column of water in its centre produces, and thus prevents it from being overset, while the man who carried it over the ice, immediately raises himself above the level of the wa- ter, and sits down in the vessel. But, in order to approach nearer to the person whose life is endan- gered, there is also employed a ladder with a long jointed handle, which is pushed forward and held by another assistant standing on the firm ice. On this ladder (which will be delineated among the implements of restoration from Drowning) the boatman places himself, and advances as near as possible to the body immersed in the water.. Having successfully exJ^atfed it, no time should be lost