I located the specifications for the two types of 3 1/2-inch iron howitzers in some material I had copied from Record Group 156 at the National Archives, Washington DC many years ago.
I'll have to find the notebook with the complete citation in it before I publish the information in a more formal way.
In any case, you can see they are contained in a letter, Morton to Wadsworth, 28 April 1813.
It seems almost as if someone had invented a larger, heavier family of howitzers, similar to the well-known 2 3/4-inch bronze King howitzers, but in iron. The designer must have been aware of the problem with the trunnions failing on the lighter version of the King howitzers, and decided to make sure that would not happen with these. If the 7-inch diameter of the trunnions given in the letter is correct, that is very large for a weapon with a 7" diameter muzzle and basering.
Do any of these unusual iron howitzers survive?
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