| Patents Granted on 1831-04-30 |
Patents 1 -
5
of 5
      |
| Number | Date | Patentee | Title | Type |
| 6,528X | Apr. 30, 1831 | J.L. Montandevert | Extracting gold from ore pulverized or amalgamating and washing residuums | |
| 6,529X | Apr. 30, 1831 | W.E. Osborn | Thrashing machine | threshers and thrashers |
| 6,530X | Apr. 30, 1831 | W.J. Stone | Polishing plates by revolving cylinders, buffs, & brushes | polishing and buffing machinery |
| 6,531X | Apr. 30, 1831 | A. Waters | Water wheel for propelling boats | nautical propulsion apparatus |
| GB-183,106,092 | Apr. 30, 1831 | R. Stephenson | Axles and parts which form the bearings at the centre of wheels for carriages to travel on edge railways | track and switches |
