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48 plates, and two pieces are then united together in the following manner:—The edges are bevelled off to the space of two or three lines, and the margins, when placed together, overlap each other to that extent. They are then pressed together by a metallic press, and the whole is submitted to the action of boiling water; and by this means the two pieces are so perfectly soldered together, as to leave no indication of the line of union. By the application of heat, also, the tortoise-shell may be made to receive any impression, by being pressed between metallic moulds.

"No portion of this precious substance is lost or useless. The filings and powder, which remain after these and the other processes to which the shell is submitted, are placed with any small fragments in metallic moulds, and by means of pressure, exercised whilst they are exposed to the heat of boiling water, they are formed into plates of any thickness which may be required."

The shell of the Turtle being so valuable, some ingenuity is well bestowed in the endeavour to avoid any waste of it. Accordingly, in manufacturing combs, a curious invention has been resorted to for this end. To make a comb six inches long, and one inch wide, one would naturally suppose that it would be needful to have a piece of shell of that size; and such is indeed the case. But two combs may be formed out of a piece of shell very little larger, by merely resorting to a very simple plan, which the