| Patents Granted on 1820-__-__ |
Patents 1 -
15
of 122
      |
| Number | Date | Patentee | Title | Type |
| 3,160X | Jan. 04, 1820 | J. Bragg | Improvement in bridges | |
| 3,161X | Jan. 10, 1820 | E. Treadwell | Bread finisher | baker |
| 3,162X | Jan. 10, 1820 | E. Crain | Making ropes and cordage | rope maker |
| 3,163X | Jan. 14, 1820 | W.W. Swain | Moulding spermaceti candles by heat applied to the moulds | chandler |
| 3,164X | Jan. 15, 1820 | W. Martin | Mortise water lock gate | |
| 3,165X | Jan. 18, 1820 | C. Williams | Improvement in railways and carriages | |
| 3,166X | Jan. 18, 1820 | Z. Chapin, S. Martin | Machine for washing, drying, and screening wheat | miller |
| NX-182,001,181 | Jan. 18, 1820 | R. Guthrie | Corn Sheller | corn shellers |
| 3,167X | Jan. 22, 1820 | C. Leek (Leck) | Raising the power of steam in steam engines without increasing the quantity | steam engines |
| 3,168X | Jan. 24, 1820 | P. Cooper | Machine for towing boats on canals | nautical propulsion apparatus |
| 3,169X | Jan. 28, 1820 | I. Town | Truss Bridge | |
| 3,170X | Jan. 28, 1820 | J. Kendall | Apparatus for preparing the oxy muriate of lime | |
| 3,171X | Jan. 29, 1820 | J. Russell | Coating for ships' bottoms | boats and ships |
| 3,172X | Feb. 01, 1820 | C. White | Water proof cement | |
| 3,173X | Feb. 17, 1820 | J. Kelly, A. Buffum | Elastic water proof hats | |
