Show usefulness of diamonds many diany persons suppose that diamonds are only used in jewelry for rings and other articles of personal adornment and that they are really of no essential value whatever in the practical arts this ibis is a mistaken notion th eyare used for a great number 0 purposes in the arts thus taus for cutting t the glass of our windows window into proper size no other substance can equi equal it and it is exclusively med for lb thijs ib purpose A natural edge or point as it Is called is used for this m rk and thousands of 0 such are tire annually required in our glatis plass factories diamond points aye arc also aso employed for on cor coT amethysts and other brilliants brilliantz brilli ants and for the finer cutting cuttin on camoes and seals being very hard t the tha I 1 ie diamond is hiso also used in chr chronometers chrono ODOmeters meters for the steps of pivots and as it possesses high refractive with I 1 interior inferior power and little lo longitudinal aberration it bas has been successfully employed for the small smail depp deep lenses of single microscopes the magnifying power of the ee diamond in proportion to that of plate glass ground round to a similar form is as 8 to 3 for fon drawing drawing minute lines iines on hard steel and and ind glass to make micrometer there is no substitute for this diamond point the rough diamond is called bort and the 11 points eints used for glass cutting are fragments of of the borts great care and skill are necessary in selecting the cutting points because the diamond that cuts the glass most successfully has the cuttin cutting edges of the crystal placed exacts exactly K at right angles to each oher and passing t through rough a point or intersect intersection 0 n made by the crossing of or the edges A polis polished h diamond however perfect maybe may be its edges when pressed upon the surface of ers it with the slightest pressure but uit tit with the natural diamond the most accurate lines linea are produced on glass and their surfaces are so finely burnished that it ruled close together they decompose decomposed light and afford the meet moist beautiful prismatic appearance all the tho colars colors of the rainbow flash from them as fronz froia the silvery interior of a peari pearl oyster au U diamonds are also employed for drill points to perforate rubies rubles and bore lore holes in draw K plates lates for fine wire and also for drilling in hard ard steel some inquiries have been made of us recently in regard to using them for dressing millstones as a substitute for steel picks we apprehend that they are altogether too toj expensive to be used for this purpose at present but if it some of our inventors would make the discovery of manufacturing diamonds as cheaply as we make charcoal which is of the same composition ave might be able to recommend them to our millers the coke obtained from the interior of gas retorts in in many cases is found so hard that it will cut glass but as ai its point endures but for a short period it cannot be made available aa as a substitute for the natural diamond for such purposes scientific american |