| All Patents in class 72/371 |
Patents 1 -
9
of 9
      |
| Picture | Number | Date | Patentee | Title |
 | 6,305 | Apr. 10, 1849 | N.C. Sanford, L.B. Smith | Machine for regulating the twist and diameter of screw-augers |
 | 13,780 | Nov. 13, 1855 | R. Cook | Dies for Making Cook's Bits |
 | 75,182 | Mar. 03, 1868 | J. Mix | Improvement in Manufacturing Gimlets |
 | 189,265 | Apr. 03, 1877 | J.C. Richardson | Improvement in Gimlets and Twist-Drills |
 | 208,862 | Oct. 08, 1878 | J. Swan | Improvement in the Manufacture of Auger-Bits |
| | 240,984 | May 03, 1881 | T.P. Farmer | Art of Manufacturing Twist Drills |
| | 315,530 | Apr. 14, 1885 | S. Moore | Manufacture of Drills |
 | 341,084 | May 04, 1886 | F.E. Whitney | Manufacture of Twist-Drills |
 | 392,119 | Oct. 30, 1888 | M. Hardsocg | Method of Twisting Augers |
