Dissolve four parts of India-rubber in thirty-four parts of coal tar naptha, aiding the solution with heat and agitation. The solution is then thick as cream, and it should be added to sixty-four parts of powdered shellac, which must be heated in the mixture till all is dissolved. While the mixture is hot it is poured on plates of metal, in sheets like leather. It can be kept in that state, and when it is required to be used, it is put into a pot and heated till it is soft, and then applied with a brush to the surfaces to be joined. Two pieces of wood joined with this cement can scarcely be sundered.