| Patents for Duff Mfg. Co., Ltd. |
Patents 1 -
10
of 13
      |
| Picture | Number | Date | Patentee | Title |
 | 292,630 | Jan. 29, 1884 | S.K. Duff, J.B. Duff | Pipe-lifter for oil-wells |
 | 293,400 | Feb. 12, 1884 | J. Barrett | Lifting-jack |
 | 312,316 | Feb. 17, 1885 | J. Barrett | Lifting-jack |
| | RE10,574 | Mar. 24, 1885 | J. Barrett | Lifting-jack |
 | RE10,651 | Oct. 13, 1885 | J. Barrett | Lifting-jack |
| | 399,470 | Mar. 12, 1889 | J. Barrett | Lifting-jack |
 | RE11,051 | Dec. 31, 1889 | J. Barrett | Lifting-jack |
 | 455,993 | Jul. 14, 1891 | J. Barrett | Lifting-jack |
 | 455,994 | Jul. 14, 1891 | J. Barrett | Lifting-jack |
 | 455,995 | Jul. 14, 1891 | J. Barrett | Lifting-jack |
