Mohs scale of mineral hardness 77 AD. While greatly facilitating the identification of minerals in the field, the Mohs scale does not show how well hard materials perform in an industrial setting. Despite its lack of precision, the Mohs scale is highly relevant for field geologists, who use the scale to roughly identify minerals using scratch kits. The Mohs scale hardness of minerals can be commonly found in reference sheets. Mohs hardness is useful in milling. It allows assessment of which kind of mill will best reduce a given product whose hardness is known. The scale is also in use at digital electronic manufacturers, for
On the Rocks (play) there is nothing new in this, since the "extermination of what the exterminators call inferior races is as old as history." What is new is that modern politicians since the French revolution have created a social principle of extermination, whether it be of aristocrats as in the case of France, or Jews as in Germany. This is an outgrowth of class conflict, but in the future such decisions can be made scientifically. On the Rocks (play) On the Rocks: A political Comedy (1932) is a play by George Bernard Shaw which deals with the social crisis of the Great Depression.