Show how hov s z diamond cuts glass it has been ascertained by a sariel of experiments that a diamond does doea not cut glass file fashion but forcest tho the particles apart so that a continuous crnek crack Is formed along the line of 0 the intended cut the crack once be gun very small force Is necessary to carry it through tho the glass and thua the piece is easily broken off tho the superficial crack or cut need not bo I 1 deep a depth according to one meas ineas ure ments of a n two hundredth part 0 OJ one inch Is quite sufficient to accomplish the purpose so that the epplin cation of much force in u ing the dla mon mond d only wears out the gem gein without doing the work any better numerous satoneg such us as quartz and other minerals when hen ground round into proper form will ill cut glass like a diamond buti they are not so valuable for that pur 1 pose lacking the requisite hard hardness nessi and soon losing tile the sharp edge feces eary to make the operation a success |