Number | Name | Date | Kind |
---|---|---|---|
1900906 | Brown | Mar 1933 | |
2320209 | Bahr | May 1943 | |
2420362 | Ekleberry | May 1947 | |
2904670 | Calmes | Sep 1959 | |
3087049 | Schecter | Apr 1963 | |
3350552 | Lawrence | Oct 1967 | |
3500037 | Starck, II | Mar 1970 | |
4638410 | Barker | Jan 1987 | |
4781422 | Kimble | Nov 1988 | |
5016151 | Mula | May 1991 | |
5180220 | Van Kalsbeek | Jan 1993 | |
5224772 | Fustos | Jul 1993 |
Entry |
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Four photographs, photos 1-4, of a conventional lock pin apparatus. |
Investigation of Permissible Electric Mine Lamps, Bulletin 441, United States Department of the Interior (1930-1940). |