This Colt Model 1851 Navy revolver was manufactured in 1866 and fitted with the extremely rare "Schenck Patent Hair Trigger Device" and stamped "PATENT" in bold lettering on the modified trigger guard. Colt Model 1851 Navy serial number 194724 fitted with a similar but not identical device is illustrated on page 132 of "THE BOOK OF COLT FIREARMS" by R.L. Wilson. A Colt Model 1860 Army, serial number 159995, fitted with an identical Schenck trigger device is pictured on page 166 of "THE BOOK OF COLT FIREARMS". Wilson states on page 132 of "THE BOOK OF COLT FIREARMS" that: "F. Schenck is known to have visited the Colt factory to show the mechanism to interested officials". He further states that the Schenck Hair Trigger Device is: "One of the most unusual accessory devices adapted to Colt arms: there are only a half-dozen models or less of the 1851 and 1860 pistols known to the authors as having the Schenck device". This revolver is a standard, Late Fourth Model 1851 Navy revolver with round trigger guard, capping channel in the recoil shield cut-out, thick loading lever catch and V-type, bevelled, loading cut-out in the barrel lug. The "PATENT" marked trigger guard is a replacement with slightly wider bow and other modifications to accept the Schenck trigger attachments. The barrel has a non-standard, dove-tail mounted, pinch-top front sight. The late style hammer has bordered knurling on the spur. The revolver components have been polished bright, the brass trigger guard and back strap have a natural finish and the one-piece walnut grip has the standard varnish finish. The top barrel flat is roll-stamped: "-ADDRESS COL. SAML COLT NEW-YORK U.S. AMERICA-" in one line. The cylinder is roll-engraved with the standard Texas Navy battle scene and "COLTS PATENT No." markings. The left side of the frame is roll-stamped "COLTS/PATENT" in two lines. The full serial number is stamped on the barrel lug, frame and back strap. The partial serial number, "97772" is stamped on the wedge and "7772" is stamped on the cylinder and cylinder pin. All of the visible serial numbers match. The loading lever and trigger guard are not serial numbered.