heated and then gradually cooled, The heavy uncut articles are thenready for the cutting operation, bywhich they lose considerable weight.In some cases the loss is one-third.The cutting operation really consistsof three stages. The article is firstroughed with sand and a steel grind-ing wheel. It…
Portland · Glass · Cement · Scientific American · Device · Cut glass · Sir william · Portland cement · American supplement · Sewing machine · Speed trials · American supplements · Jerome park · Shunt coil
Internet Archive · Public Domain Mark 1.0. Free to use for anything.