U.S. patents covering time keeping mechanisms (1892)
United States. Patent Office · [Washington : United States Patent Office] · leaf 69
d \<\m\~j5 L m.iHi. PCTER8 CO., PHOTO-UTMO., WASHINGTON. D. C. (No Model.) No. 474,871 W. G. SPIEGEL. TIME LOCK. 2 Sheets—Sheet 2. Patented May 17, 1892. … y F i c .7. P-...J \ / \4
Clocks and watches
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