US Patent: 1,422,345
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Trammel
Ellipse Drawing Tool
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Patentee:
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| William Douglas (exact or similar names) - Pawtucket, RI |
| USPTO Classifications: |
| 33/31 |
| Manufacturer: |
| Not known to have been produced |
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Patent Dates:
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| Applied: |
May 07, 1921 |
| Granted: |
Jul. 11, 1922 |
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Ralph Brendler
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Description: |
| This is an ellipsograph that is designed to attach to a normal framing square. The claims recommend it as being particularly useful to stair builders. |
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