Experimental science. Elementary, practical and experimental physics (1890)
Hopkins, George M. (George Milton), 1842-1902 · New York, Munn & co. · leaf 689
, and is finally ground into the concave toolwith washed flour emery and water. A tool like that shown at 6 is necessary for finishingsmall lenses. It consists of a cylindrical piece of brass hav-ing a chamber turned in the end for the reception of a mix-ture of pure hard beeswax and fine rouge.… … Tools for Grinding Small Lenses. plate (crown) glass and roughly shaped by means of an ordi-nary pair of phers. It may then be cemented with pitch tothe end of a round stick, as shown at 7 The glass is then MECHANICAL OPERATIONS. 66/ ground on a common grindstone until it approximates therequired…
Physics · Lantern projection · Electric apparatus and appliances
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