| Patents Granted on 1831-04-?? |
Patents 1 -
15
of 92
      |
| Number | Date | Patentee | Title | Type |
| 6,440X | Apr. 01, 1831 | J. Tousey (Tonsey), G. Cande | Thrashing machine | threshers and thrashers |
| 6,441X | Apr. 01, 1831 | H. Knowles | Improved mode of manufacturing wood-screws | screw machines |
| 6,442X | Apr. 01, 1831 | J. Powell | Washing gold ores and alluvial auriferous earth | |
| 6,443X | Apr. 04, 1831 | C. Madison | Circular saw for sawing laths | circular saws |
| 6,444X | Apr. 05, 1831 | M.D. Mulford | Washing machine | washing machines |
| 6,445X | Apr. 05, 1831 | R. Wilcox | Metallurgical operations by chemical agents | trade specific |
| 6,446X | Apr. 05, 1831 | R. Wilcox | Metallurgical operations by anthracite coal | trade specific |
| 6,447X | Apr. 05, 1831 | R. Wilcox | Metallurgical operatons by bituminous coal, charcoal | trade specific |
| 6,448X | Apr. 06, 1831 | J. Ames | Machine for washing rags | washing machines |
| 6,449X | Apr. 06, 1831 | S. Boyden | Manufacturing malleable cast iron | trade specific |
| 6,450X | Apr. 06, 1831 | S. Lane | Thrashing machine | threshers and thrashers |
| 6,451X | Apr. 06, 1831 | R. Tenney, E. Mudge | Scoop shovel | shovels |
| 6,452X | Apr. 06, 1831 | J. Scott | Glass frame for pictures | |
| 6,453X | Apr. 06, 1831 | W.A. Turner | Preventing explosion of boilers and burning | stationary boilers |
| 6,454X | Apr. 07, 1831 | R.M. Beach | Boiling liquids of all kinds | |
