[gyvel]

All the Deane Adams and Deane I have seen have been double action only guns; However, there was a Tranter patent ca. 1856 that used a primary trigger to first cock the revolver, and a secondary trigger to fire. The mechanism used on your DAD may have been inspired by Tranter's patent, or possibly even designed by Tranter himself. It seems that all of these designers were well acquainted with each other and often worked together.

Photos of DAD revolvers in one of my reference works are listed as "Model 1851," and appear identical with your specimen with the exception of the trigger mechanism. Since all shown have standard DAO triggers, they also have trigger guards. The type of mechanism on yours would preclude the use of a trigger guard. I suspect you have a rather unusual example of a DAD.

This type of mechanism is not entirely unknown; The Savage pistol (Henry S. North and Edward Savage of Middletown, CT) purchased by the Union Army utilized a similar mechanism. A lower ring shaped trigger cocked the pistol, which was then fired by an upper, conventional trigger

There was, ca. 1855 a Beaumont-Adams revolver that introduced what can best be referred to as a "hesitation action." It allowed the revolver to be cocked, but, when cocked, required that the shooter release the trigger slightly, at which point it would reset the sear, allowing a second (lighter) pull on the trigger to release the hammer and fire the gun. Even with this mechanism, it was still only a single trigger gun, however.

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