EARTH COLOURS 54 necessary is to destroy the cohesion of the particles, as is the case, for example, with clay and all earthy minerals. The wet method of crushing with edge runners is … FIG. 9. particularly suitable as a preliminary to levigation. A machine arranged for this purpose is shown in Fig. 8. It consists of two sets of edge runners, one with fixed, and the other with revolving trough. The material is introduced by hand, or by suitable charging mechan-
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Internet Archive · Gerstein - University of Toronto · Public domain (published before 1931). Free to use for anything.
