Summary

Birch's key, cylindrical, fluted. Adjustable to fit different sized winding arbors.

Physical Description

PATENTED BY JOHN S. BIRCH. U. S. PATENTS 13:4:1869, 23:5:1876. MOSTLY USED BY WATCHMAKERS. KEY MADE BY MANY MAKERS WHEN PATENTS EXPIRED AND MOSTLY OF INFERIOR METAL. THIS IS EVIDENTLY ONE OF THE LATER EXAMPLES.

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