Mastic Cement is used for making a superior coating to inside walls, and which must not be confounded with the resin stlic. It is made by mixing twenty parts of well-washed and sifted sharp sand with two parts of litharge and one of freshly burned and slaked quicklime in fine dry powder. This is made into a putty, by mixing with linseed oil; it sets in a few hours, having the appearance of light stone; and we mention it, as it may be frequently employed with advantage in repairing broken stonework (as stairs) by filling up the missing parts.