104,472. Phillips, R. E., (Honeyman, J. N., and Watson, P. H.). Sept. 27, 1916. Roads, special materials for; macadamized roads.-Consists in rendering the surface of a road dustless by treating it with a mixture of finely-ground " salt crust " and pulverized slag or stone. The material salt crust is the scale that is periodically removed from the pans in which brine is converted into common salt. The preferred proportions are one part by volume of salt crust to three parts by volume of stone. The mixture is placed on the prepared road surface and damped, so that by subsequent rolling, it may be thoroughly grouted in.