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The only descriptions that I have seen for the williams gun carriage state that they were mounted on a carriage lighter than a Mt. Howitzer carriage. This is certianly that.
It is interesting that this is the gun which was stolen from ScHoolfeild's Battery (of 6 Williams guns) by a yankee scout in Tennesse. He crept into camp and lifted the gun off the carriage and hid it in the bushes.
(in the photo you can see the pin extending below the carriage under the yoke) When he return to recover the gun after the Rebs moved out the next morning, he found that they had left the carriage for which they had no barrel. he remounted the barrel and took it away. This gun was then sent to Frankfort Arsenal(ky).
A later incident has the Officer who was in cammand, Col. Johnson riding through camp and seeing a soldier standing near one of schoolfeilds little guns; decided to address him for the ammusment of his fellow officers by saying
"soldier, you had better watch those little guns; a woman might come into camp and carry one off. The soldier replied" I dont think that they are in any danger. Old Col. Tom Johnson is not in command here now." CVM 1909