American horological journal, devoted to practical horology (1869)
Miller, George B · New York, G. B. Miller · leaf 238
; an angle of 45° then makesthe point rather weak, and it will be best to de-crease it. It must be understood, however, thatunless the plan angle is greater than 60°, itwill be impossible to obtain two cutting edgesof the necessary acuteness. Tools are often made with the point roundedoff, as in… … which represents an oblique section of arounded tool, made at an angle of 45°. Thehighest part of the edge A, will be exactly atthis angle ; the lowest, however, will be at anangle of 135°. Between these two points therewill be every intermediate gradation. Thus at Iand m it will be 90°, so that…
Clocks and watches
Internet Archive · Smithsonian Libraries · Public Domain Mark 1.0. Free to use for anything.
