U.S. patents covering time keeping mechanisms (1892)
United States. Patent Office · [Washington : United States Patent Office] · leaf 535
(jt^A^^?LLr<<j( Ocv^iauaJI a^« CC(/L9*-viAjt^ya— HE WORBIS PETE*S CO. PHOTO-LITMO (No Model.) 17 Sheets—Sheet 4. G. E. HUNTER. MECHANISM FOR TESTING WATCH BALANCES AND HAIR SPRINGS. No. 490,202. Patented Jan. 17, 1893. <%<* O o £ … %*■
Clocks and watches
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