The Chicago Firearms Company bought the patent form the Minneapolis Firearms Company in 1892 and produced 12,800 examples of the peculiar pistol form 1894 through 1896. This model had a refinement of having an added safety catch that looked much like a trigger on the front of the gun, which the earlier Minneapolis and French gun lacked. The Chicago model also had a seven in its doughnut cylinder. These guns were manufactured by the Ames Sword Company of Chicopee Falls, Mass. The first models were supposed to be delivered in time to show at the Chicago World’s Fair, but Ames defaulted and was sued by The Chicago Firearms Company. Ames lost the suit and paid a substantial sum and became the owner of 12,800 pistols they did not want. They were sold on the market as late as 1910 in some cases, although all of them were made before 1898. These models were larger than the petit Minneapolis Firearms Company pistol because they were made as ten shot models (larger doughnut) rather than the earlier seven shot models of the previous company, although in the same caliber.
See also my blog entries: APACHES ... IN PARIS? and APACHES IN PARIS? PART II for the first two parts of the series, plus an article on the Le Mat revolver called STEAMPUNK MINICANNONS ARE REAL .