Pocket Watch Database
Patent Archive
#2131915
Patent Information
Clock Secondary
Bert Chapman Chapman
October 4, 1938
Patent #2131915
| Patent Number: | 2131915 |
| Description: | Clock Secondary |
| Inventor(s): | Bert Chapman Chapman |
| Assignee: | Ibm Corp |
| Patent Date: | Oct 4, 1938 |
| Registration Type: | Patent |
| External Research: | https://www.google.c… |
| Patent Document: |
