U.S. patents covering time keeping mechanisms (1892)
United States. Patent Office · [Washington : United States Patent Office] · leaf 581
i4~. … 0ftvt/&ritiri/. £. THE MOKRIS JTTERS CO. PHOTO-LITMO,, WASHINGTON. I (No Model.) 10 Sheets—Sheet 8. G. E. HUNTER. METHOD OF TESTING WATCH BALANCES AND HAIR SPRINGS. No. 490,203. Patented Jan. 17, 1893.
Clocks and watches
Internet Archive · Smithsonian Libraries · Public Domain Mark 1.0. Free to use for anything.
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