| Patents Granted on 1821-03-?? |
Patents 1 -
15
of 15
      |
| Number | Date | Patentee | Title | Type |
| 3,306X | Mar. 03, 1821 | T.L. Jennings | Dry scouring clothes | clothes drying machine |
| 3,307X | Mar. 03, 1821 | S. Hart | Cutting boots and shoes by rule | |
| 3,308X | Mar. 09, 1821 | B.L. Oliver | Anti-friction crank for steam engines | steam engines |
| 3,309X | Mar. 19, 1821 | T.B. Robbins | Making aqueduct pipes | pipes |
| 3,310X | Mar. 20, 1821 | J. Aborn | Machine for dipping candles | candle making machinery |
| 3,311X | Mar. 20, 1821 | P. Laporte | Bridle for stopping horses when running away | bridles |
| 3,312X | Mar. 20, 1821 | A. Cock | Machine for planting indian corn | |
| 3,313X | Mar. 20, 1821 | R. Hunt, II | Hooping or tiring carriage wheels | wheelwright |
| 3,314X | Mar. 21, 1821 | A.O. Stansbury | Spiral Lever Press | lever presses |
| 3,315X | Mar. 23, 1821 | C. Dean, S. Shepard | Ball speeder for roping cotton | spinner |
| 3,316X | Mar. 28, 1821 | R. Greaves | Top sled for cordage | rope maker |
| 3,317X | Mar. 28, 1821 | M. Ward | Steam engines | steam engines |
| 3,318X | Mar. 28, 1821 | N. Lindsey | Corn shelling machine | miller |
| 3,319X | Mar. 29, 1821 | R. Bulkley | Machine for protecting firemen | |
| 3,320X | Mar. 30, 1821 | J. Gregg | Machine for threshing and cleaning grain | miller |
