In the aftermath of their rejection in the US 1907 pistol trials, Joseph White and Samuel Merrill continued working on handgun designs. In 1911, Merrill wrote to the Ordnance Department to inquire about whether they would be interested in testing his new design. While the Department was willing, Merrill and White never ended up submitting the gun - probably because of a combination of fine-tuning problems and the formal adoption of the Colt/Browning Model 1911 as the new US service pistol.
This 1911 model White-Merrill was a complete mechanical departure from their previous 1907 trials pistol. It uses a delayed blowback mechanism, relying on a heavy mechanical disadvantage when cocking the hammer to delay the opening of the slide. The patent for this pistol (https://patentimages.storage.googleapis.com/pdfs/0e334770f75a39338542/US1052394.pdf) describes several different mechanisms for an action that would function equally well without regard to the pressure of the cartridge, but these claims seem dubious to me - rather like the theoretical principle of the Blish lock in the Thompson.
At any rate, it is very interesting to be able to examine the gun - it is the only example made by White and Merrill. Their handguns designs would find no commercial success, but White would go on to submit several interesting rifle designs to compete with the Garand in the late 1920s.
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