This is an extremely rare example of a U.S. Model 1907 semi-automatic pistol submitted by Colt for the U.S. Army "Test Trials" in 1907. This pistol is one of only 200 actual pistols manufactured under the Army Contract of 1907 for field trials, with an additional five made for presentation. This pistol, serial number 91, was shipped from Colt to the Springfield Armory on March 17, 1908, and was one of the 64 pistols issued to Troop H, 2nd Cavalry Regiment at Fort Des Moines, Iowa, for actual evaluation. Due to numerous design and/or manufacturing deficiencies found during the initial test firing of the field trials, in June 1909, Colt submitted a letter to the Chief or Ordnance, requesting to withdraw all of their test samples, agreeing to modify them to correct/improve the initial deficiencies and then returning them to the Army for further evaluations. As noted on page 35, in Clawson's book, "Colt 45 Service Pistols", this specific example, serial number "91", was one of those withdrawn, modified and reissued for further testing by the 2nd Calvary Regiment at Fort Des Moines, Iowa. It is also mentioned by serial number on page 83 of "U.S. Military Automatic Pistols 1894-1920" by Meadows. These 1907 "Test Trials" pistols are extremely rare and very important pistols for both Colt and U.S. martial pistol collectors from two aspects: One, this was the first U.S. Army contract pistol that was chambered in the ever popular 45 ACP cartridge. Although replaced in 1985 by the 9mm round for the new U.S. service pistol, this cartridge is still being used by the U.S. Military Special Operations Command in several pistols employed today. Two, this pivotal 1907 design and the subsequent modifications lead directly to the development of the all-time favorite U.S. Army Model 1911/1911A1 pistols that were in service for over 74 years. This is certainly an extremely important link in any U.S. martial arms pistol collection. The right side of the slide is roll-stamped "AUTOMATIC COLT/CALIBRE 45 RIMLESS SMOKELESS" in two lines, and the left side is marked "PATENTED/APR. 20, 1897. SEPT.9.1902. DEC.19.1905." in two lines followed by "COLT'S PATENT FIRE ARMS MFG. CO./HARTFORD. CONN. U.S.A." The serial number "91" is located on the left side of the frame above the trigger guard bow, which has the initials of Ordnance inspector "K.M." (Major Kenneth Morton). This pistol won Silver Medal number 324 awarded by the NRA for one of the ten best arms exhibited (medal not included with lot). Provenance: The Dr. Joseph Murphy Collection; Property of a Gentleman