SOLID EMERY WHEELS.—By T. D. Paret.—Early forms of emery wheels and their defects. Vulcanite wheels. The tanite wheels. Testing of tanite wheels at Stroudsburg. Best working speeds for emery wheels. Bursting of emery wheels. Tests for emery wheels. Comparative merits of American and English emery wheels. With 2 engravings. Contained in Scientific American Supplement, No. 538. Price 10 cents. To be had at this office and from all newsdealers.
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