To prevent the soup from burning to the boiler, the bottom of the boiler should be made DOUBLE; the false bottom, (which may be very thin) being fixed on the inside of the boiler, the two sheets of copper being every where in contact with each other; but they ought not to be attached to each other with solder, except only at the edge of the false bottom where it is joined to the sides of the boiler.--The false bottom should have a rim about an inch and a half wide, projecting upwards, by which it should be riveted to the sides of the boiler; but only few rivets, or nails, should be used for fixing the two bottoms together below, and those used should be very small; otherwise where large nails are employed at the bottom of the boiler, where the fire is most intense, the soup will be apt to BURN TO; at least on the heads of those large nails. The two sheets of metal may be made to touch each other every where, by hammering them together after the false bottom is fixed in its place; and they may be tacked together by a few small rivets placed here and there, at considerable distances from each other; and after this is done, the boiler may be tinned. In tinning the boiler, if proper care be taken, the edge of the false bottom may be soldered by the tin to the sides of the boiler, and this will prevent the water, or other liquids put into the boiler, from getting between the two bottoms. In this manner double bottoms may be made to sauce-pans and kettles of all kinds used in cooking; and this contrivance will, in all cases, most effectually prevent what is called by the cooks burning to[9]. The heat is so much obstructed in its passage through the thin sheet of air, which, notwithstanding all the care that is taken to bring the two bottoms into actual contact, will still remain between them, the second has time to give its heat as fast as it receives it, to the fluid in the boiler; and consequently never acquires a degree of heat sufficient for burning any thing that may be upon it. Perhaps it would be best to double copper sauce-pans and small kettles throughout; and as this may and ought to be done with a very thin sheet of metal, it could not cost much, even if this lining were to be made of silver. But I must not enlarge here upon a subject I shall have occasion to treat more fully in another place.--To return, therefore, to the subject more immediately under consideration, Food. CHAPTER. IV. Of the small expense at which the Bavarian soldiers are fed. Details of their housekeeping, founded on actual experiment. An account of the fuel expended by them in cooking.