Pocket Watch Database
Patent Archive
#437345
Patent Information
Machine Watch Balance Spring Apparatus
Edwin J. Hall
September 30, 1890
Patent #437345
| Patent Number: | 437345 |
| Description: | Machine Watch Balance Spring Apparatus |
| Inventor(s): | Edwin J. Hall |
| Patent Date: | Sep 30, 1890 |
| Registration Type: | Patent |
| External Research: | https://www.google.c… |
| Patent Document: |
