It is obvious that seats, cushions, pillows, and beds of various kinds, having a similar object in view in respect to softness, fulness, and elasticity, May be made by similar means. When the quantity of air included in an envelope is greatly increased, it may be made the meant of producing actual pressure in a more equable way than by any solid bodies. Thus, an air-tight bandage, so formed, is often Used in surgical operations.
The patents for caoutchouo waterproof materials taken out by Mr. Hancock, Mr. Sieviet, and other inventors, within the last few years, are to exceedingly numerous that we can only speak of them generally. One patent is for cutting cotton and other fibres into very small fragments, mixing them with dissolved caoutehouc, and forming sheets of material from this mixture. Another patent relates to a method, in which very thin sheets Of caoutchouo fire cemented by a solution of caoutchene to gauze, bobbin net, or other Open material; and on this, as a ground, and with a similar Cement of quick-drying ca-out chouc, is laid a stratum of fibres. The fibres are pressed and dressed; and the open and extensible meshes of the gauze or bobbin-net give to the whole an elasticity which closely- woven textures cannot impart.
The attempts to render leather waterproof depend in general on the filling up of the small pores which have previously admitted the tannin, the substance imbibed being such as will repel or resist water. Many such compositions have been proposed at different times, of which the mention of a few will here suffice. Melt over a slow fire a quart of boiled linseed oil, a pound of mutton suet, three-quarters of a pound of yellow bees' wax, and a half a pound of common resin, or smaller quantities in the like relative pro portions; and with this mixture saturate the leather of new boots or shoes, while the latter is slightly warm. Another method is to melt two ounces of yellow beos'-wax, two ounces of Burgundy pitch, and two ounces of turpentine, in a pint of linseed oil, and with this mixture to saturate the warm leather. Another mix ture for this purpose consists of six ounces of eaoutchouc boiled for two hours in two quarts of linseed or neat's-foot oil. Lastly, a mode has been much recommended of applying a hot mixture of two parts tallow and one part resin, with which the leather may be com-1 pletely saturated, the resin imparting an antiseptic quality to the tallow.