Glue, Marine

Prep. 1. India rubber (cut small), 1 part; coal tar or mineral naphtha, 12 parts; digest in a covered ve el with heat and agitation, and when the solution is complete, add of powdered shell-lac, 20 parts; continue the heat and stirring until perfect liquefaction has taken place, and pour the fused ma , whilst still hot, on slabs of polished metal or stone, so as to form thin sheets. For use, it is heated to its melting-point (248° to 250° Fahr.) in an iron ve el, and applied in the liquid state with a brush. Employed in ship-building, . 2. Caoutchouc, 15 to 20 gr.; chloroform, 2 fl. oz.; di olve, and add of powdered mastic, 1 ⁄ 2 oz. It must be kept well corked and in a cool place, to prevent lo by evaporation. Used for small, fine work.