| Dynamo-electric machine : specification forming part of letters patent No.297, 587 | |
| 1884 |  |
| Thomas Alva Edison(1847-1931) | |
|
|
| Dynamo-electric machine : specification forming part of letters patent No.297, 587 | |
| 1884 | |
| Thomas Alva Edison(1847-1931) | |
|
|