Marking are showing up with light cleaning. On barrel: COLT D.A .38. on frame just below cylinder: Pat: SEPT 18,1871, "JUN 5,1874, "JAN 19,1875. No serial No.? It's soaking in some white vinegar. When it's clean I'm going to dry it thouroghly and take it to a gunsmith for disassembly. The rust...