Appleton's dictionary of machines, mechanics, engine-work, and engineering (1861)
Appleton, firm, publishers, New York. (1852, D. Appleton & Co.) · New York : D. Appleton · leaf 663
It frequently happens that certain forged, cast, and other works have parts, known as bosses, swells,eollars, and knuckles, that are pierced with holes, which require their flat surfaces and also their mar-gins to be made partially or entirely concentric with the holes. When such parts occur as… … When the circular margins are discontinuous, files and templets are more or less required: thus theextremity of a forged arm, such as Fig. 1691, is drilled, and in the configuration of the remaining parts,if but one or two such pieces are to be made, a boss or plug of wood is turned like a, that…
Mechanical engineering
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