Instead of the old division of the right angle in 90 of 60' at 60" each, the following division finds ever more frequent application: one quadrant has 100 grades (gr), which in their turn are sub- divided decimally in decigrades (dgr), centigrades (cgr), milligrades (mgr) and decimilligrades (dmgr). In using instruments upon which the quadrant is divided into 100 equal parts, in working with a calculating machine or a slide rule the new division...