The cannon is a cast iron 24 pounder, flank howitzer made for use in Sea Coast forts by the U.S. Army. It is one of 300 such guns made between 1846 and 1849. They were ordered in 1845 at a cost of 9 cents per pound. Three orders of 100 guns each were placed with foundries in the United States.
These guns were not mounted on field carriages with large wheels, but were on slanted, semi-permanent carriage with small wheels for use in fortresses.
The following is an explanation of the markings on this gun:
The number 81 stamped on the top arc of the muzzle is the government registration number of this cannon. This is one of 30 guns inspected and accepted for government use on July 8, 1846. They were numbers 52 thru 81.
The initials J.W.R. stamped on the Lower arc of the muzzle are those of James Wolfe Ripley, the Ordnance Inspector who accepted the cannon for the U.S. Army on July 8, 1846. He was later Chief Ordnance Inspector for the U.S. Army.
The C.A. & Co. stamped on the center of the right trunnion stands for Cyrus Alger & Company, a South Boston, Massachusetts foundry where this gun was cast.
The 1846 stamped on the center of the left trunnion is the year this gun was cast.
The small number 292 stamped just above the left trunnion is an internal control number of the foundry.
The U.S. stamped on the top center of the gun shows the piece has been accepted by the U.S. Government.
The number 1482 stamped on the lower rear of the gun is its weight in pounds. At a price of 9 cents per pound, this gun cost the U.S. Government $133.38 on July 8, 1846.
This gun was most likely never fired in anger, as it spent its entire useful life in a fort somewhere in New England, guarding our coast.
This information was obtained from research done by Wayne Stark on all existing cannons of the Civil War era. He used the Ordnance Archives of the United States Army and Navy to establish a computer listing of all known guns that may still be in existence, and then has checked on their actual location. He checked this gun while his son was a student at the Air Force Academy.