| All Patents in class 451/375 |
Patents 1 -
10
of 50
      |
| Picture | Number | Date | Patentee | Title |
 | 104,982 | Jul. 05, 1870 | S.A. Morse | Improvement in grinding-rest for twist-drills |
| | 141,760 | Aug. 12, 1873 | S.W. Card | Machines for milling twist-drills |
 | 153,401 | Jul. 21, 1874 | C. Van Haagen | Improvement in machines for sharpening twist-drills |
 | 183,798 | Oct. 31, 1876 | A.F. Champlin | Improvement in Tools for Sharpening Drills |
 | 201,449 | Mar. 19, 1878 | A.K. Rider | Drill Grinder |
| | 230,715 | Aug. 03, 1880 | I.L. Penney | Grinding Twist Drills |
| | 299,433 | May 27, 1884 | A. Coventry, W.F. Smith | Machinery for Grinding or Sharpening Drills |
 | 388,784 | Aug. 28, 1888 | F. Mossberg | Twist-drill-grinding attachment |
 | 389,095 | Sep. 04, 1888 | F. Mossberg | Twist-drill-grinding attachment |
 | 407,577 | Jul. 23, 1889 | J.D. Cox, Jr. | Machine for back-clearing twist-drills |
