HAWLEY

It should should probably be named the "Hawley" after Edwin H. Hawley, its inventor and maker, but it has been affectionally known by the delightfully sounding location of manufacture. Regardless, no title or markings appear on the pistol itself.
The "Kalamazoo" has special historical significance: it is purported to be America's first commercial pneumatic pistol. (Lukens & Kunz made pneumatic rifles in the Philadelphia area from 1800-1815 but did not make pistols.) It was based on patent #90,749, which was issued June 1, 1869 to Hawley, but ultimately covered by the improved patent #118,886, which was issued to Edwin Hawley and George Snow on September 12, 1871.
The original patent described a butt-reservoir pneumatic with a straight pump affixed under the barrel and a hammer (suggestive of a flightlock hammer with sear mechanism) fully visible on the bottom curve. The improved patent included the appearance of the front sight by merely turning up a section of the front barrel band. The sight arrangement was strikingly strange: a valve release pin protrudes from the top center of the receiver, thus the rear sight groove is displaced to the right. To sight the gun, one must tip it about 45 degrees to the left.
The cast iron receiver contains the air reservoir in the butt and firing mechanism in the forward parts. The gun hosts 3 large casting holes sealed by pewter/ lead or by brass plugs. Brass plug ahead of trigger allows access to install and repair the exhaust valve.