US Patent: 1,447,913
|
| Recording Indicator
|
|
Patentees:
|
| Augustus Trowbridge (exact or similar names) - Washington, DC |
| William C. Duryea (exact or similar names) - Princeton, Mercer County, NJ |
| Manufacturer: |
| Not known to have been produced |
|
|
Patent Dates:
|
| Applied: |
Oct. 05, 1920 |
| Granted: |
Mar. 06, 1923 |
USPTO (New site tip) Google Patents
Report data errors or omissions to steward
Joel Havens
|