Appleton's cyclopædia of drawing, designed as a textbook for the mechanic, architect, engineer, and surveyor (1866)
Worthen, William Ezra, 1819-1897, [from old catalog] ed, Appleton, firm, publishers, New York. (1866. D. Appleton & co.) [from old catalog] · New York, D. Appleton and company · leaf 260
Fig. 2S0. … tended to ha flush or even with the surface of the j^iece into which the boltis inserted, the inside of the head is made conical like the common wood- 192 DRAWING OF MACHmERY. screw, or pyramidal, and it is then said to be countersunk. When boltsare employed in wood, washers are usually placed…
