| Patents Granted on 1838-04-?? |
Patents 1 -
15
of 18
      |
| Number | Date | Patentee | Title | Type |
| 664 | Apr. 02, 1838 | R. Savary | Machine for Making Wrought Spikes and Nails | specialty woodworking machines |
| 667 | Apr. 02, 1838 | O. Wright, A.A. Wright | Rotary steam-engine | rotary steam engines |
| AI3 | Apr. 04, 1838 | J. Heberling, W.E. Lukens, H. Heberling, A. Trahern | Horse Power | animal powered apparatus |
| 681 | Apr. 07, 1838 | R. Daniels | Crosscut eclipse shearing-machine for shearing woolen cloths | cloth shearing machines |
| 684 | Apr. 07, 1838 | T. Burdick, F. Burdick | Machine for mortising timber, &c. | mortising machines |
| 685 | Apr. 07, 1838 | I. McLaughlin | Machine for mortising timber, &c. | mortising machines |
| NS-6 | Apr. 09, 1838 | D.H. Dickey | Instrument for drawing teeth | dental tools |
| 694 | Apr. 14, 1838 | C. Learned, S. Waterman | Brick Machine | brick and tile making machines |
| RE2 | Apr. 16, 1838 | W. Keane | Improvement in Machines for Cutting Wood and Other Screws | screw machines |
| 695 | Apr. 16, 1838 | J.R. Wheeler | Water Wheel | water wheels |
| 699 | Apr. 21, 1838 | D.C. Stone | Machine for manufacturing axes | tool making machines |
| 700 | Apr. 21, 1838 | J.C. Yates | Sawmill without saw-gate | reciprocating sawmills |
| 714 | Apr. 28, 1838 | J. Secor | Horse Power | animal powered apparatus |
| 715 | Apr. 28, 1838 | J. Mumma | Water Wheel | water wheels |
| 716 | Apr. 28, 1838 | H. Barnes | Machine for mortising and tenoning timber, &c. | mortising machines |
