Originally manufactured in 1910, this is an example of the extremely rare Colt Model 1910 prototype pistol, an extremely important evolutionary piece in the story of the adoption of the Model 1911 by the U.S. military. There were possibly as few as eight of these pistols ever made, possibly as many as 12, making them incredibly rare and often a missing piece in U.S. military automatic pistol collections. These pistols were initially manufactured to be an improvement upon the "straight-gripped" Model 1909. They were initially submitted for testing on 9 February 1910, when Captain Walter G. Penfield described the "improved model" as having the mainspring cap simpler, smaller, and attached to the spring, extractor inside the breech, ejector made square, angle of the grip changed, the sear, trigger, and grip safety springs made in one piece, butt of the grip sharply angled instead of rounded, barrel slightly lowered, and the ejection port slightly enlarged. Even with all of these "improvements", the pistol failed it's initial test fairly miserably, jamming seven times in the first 157 shots, and John Browning withdrawing it from the test to try to improve the design. The second test occurred five days later, with the pistol operating much better this time, only having one misfire in 1,000 shots. It still wasn't perfect however, as Browning had to straighten the recoil spring retaining piece multiple times, and it eventually broke completely. Browning believed this was due to the piece being made too thin and of inferior steel, an issue that could easily be remedied. In July of 1910, a special grip was requested by the ordnance department, the main feature of which being a smooth right panel which slightly swelled into the palm. The special grip was tested by the School of Musketry, who did not favor the "improved" grip over the original checkered grips. In August of 1910, two Model 1909 pistols were fitted with thumb safeties, which the Ordnance Department found favorable, especially for use with mounted troops. On 10 November 1910, the Ordnance Board met to pit the Model 1910 Colt and Savage pistols against each other for the second to last time, with the main feature of this trial being an endurance test, with 6,000 rounds fired through each. After this trial the Board's assessment was that "That neither automatic pistol in its present design is believed to be satisfactory for adoption in the service because of insufficient strength of parts... The Colt automatic pistol is believed to be much the more satisfactory of the two." One of the issues with the Colt pistol which was found during this specific trial, was that the grip screws continually worked themselves loose when subjected to sustained fire. It is quite possible that the knowledge of this, along with his continual work towards minimizing the number of parts and number of tools needed for assembly and disassembly, that prompted John Browning to modify the grips on this specific example, the patent for which is dated 19 August 1913. After the issues with both of these pistols in the final test of 1910, the Chief of Ordnance decreed that another series of tests would be held on 15 March 1911. To this test, Colt submitted the Model 1911 Special Army, a design which was approved for adoption by the U.S. military on 29 March 1911. This specific pistol is pictured and discussed on p. 116-117 of "The Government Models: The Development of the Colt Model of 1911" by Goddard and on p. 108 of "U.S. Military Automatic Pistols 1894-1920" by Meadows/Ellis. The left side of the slide on this pistol is marked with the two-line two-block patent dates (ending with 1905) and Colt address while the right side has the two-line caliber marking. The left side of the frame has the single digit serial number "3" and there are no visible inspectors markings or proofs. It is fitted with blade and rounded top notch rear sights, a long smooth trigger, checkered slide stop, a short grip safety, and a straight smooth mainspring housing with the lanyard ring staple removed from the base. It was not fitted with the thumb safety that some of the other Model 1910 prototypes and later the Model 1911 received. It is also fitted with the unique grips which are retained by studs on the frame and slots in the grips rather than screws for ease of disassembly. Grips very similar to this were incorporated for a short time on prototypes of the Fabrique Nationale "Grand Browning", which was a scaled down version of Browning's design which was intended for submission for adoption by European militaries. The development of this pistol was disrupted by the outbreak of World War I however, and only a small number were ever manufactured. This pistol is furnished with an unmarked two-tone pinned base magazine with a lanyard ring on the base. Included with the pistol are copies of Browning's patents which apply to it as well as copies of a letter which describes the features of the pistol in depth. Provenance: The Dr. Robert Azar Collection