Sargent Mortise Lock: A complete mortise lock case stamped "SARGENT, NEW HAVEN, CONN. P. & F. Corbin Mortise Lock: A mortise lock case marked "P. & F. CORBIN, NEW BRITAIN, CONN. U.S.A." with patent dates "PAT JAN 20 99" and "JUNE 11 99," indicating it was manufactured around 1899.
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