American horological journal, devoted to practical horology (1869)
Miller, George B · New York, G. B. Miller · leaf 88
ll bow; whetherthe angle is to be acute or obtuse, or the endbe slightly rounded, must be determined bythe circumstances of the case, the materialupon which it is to operate, and the positionin which it is to be used. The action isscraping rather than cutting in all such ascut in both directions.… … drill, made of wire filed down to the diame-trical line, and as far back as it is intended topenetrate ; the end is formed with two faces;it has the advantage of not having the diame-ter changed by being sharpened ; it may bepointed circular or flat, and will remain cen-tral • it is sometimes…
Clocks and watches
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