| Patents for W. & B. Douglas |
Patents 16 -
30
of 30
      |
| Number | Date | Patentee | Title | Type |
| 97,767 | Dec. 14, 1869 | J.W. Douglas | Improvement in pumps | household hand pumps |
| 97,894 | Dec. 14, 1869 | J.W. Douglas | Improved apparatus for extinguishing fires by means of chemical agents | fire extinguishers |
| 98,674 | Jan. 11, 1870 | J.W. Douglas | Improvement in adjustable attachment of pump-barrels to their bases | household hand pumps |
| 102,664 | May 03, 1870 | J.W. Douglas | Improvement in pump-valves | household hand pumps |
| 134,294 | Dec. 24, 1872 | J.C. Lamb, E. Lavens | Improvement in rotary pumps | rotary pumps |
| 144,965 | Nov. 25, 1873 | J.W. Douglas | Improvement in pumps | household hand pumps |
| 151,364 | May 26, 1874 | J.W. Douglas | Improvement in the construction of pump-gearing | household hand pumps |
| 158,786 | Jan. 19, 1875 | J.W. Douglas | Lining pump cylinders | household hand pumps |
| 166,195 | Aug. 03, 1875 | J.W. Douglas | Improvement in water-hydrants | hydrants |
| 173,601 | Feb. 15, 1876 | J.W. Douglas | Improvement in vehicle-wheels | wheelwright |
| 192,979 | Jul. 10, 1877 | J.W. Douglas | Improvement in portable pumps | household hand pumps |
| 244,384 | Jul. 19, 1881 | J.W. Douglas | Pump | household hand pumps |
| 294,210 | Feb. 26, 1884 | J.W. Douglas | Pump | household hand pumps |
| 306,679 | Oct. 14, 1884 | J.W. Douglas | Pump | household hand pumps |
| 386,115 | Jul. 17, 1888 | E. Douglas | Telescopic stop-cock for water-service | water valves |
