Rodman's 20-inch Cannon Cast at Fort Pitt Foundry-- Part 1

From the february 21, 1864 New York Times (from the February 12, 1864, Pittsburgh Chronicle "A Twenty-Inch Gun.; Casting  at the Fort Pitt Foundry."

"One of the most important events in the history of the rebellion, and which inaugurates a new era in the manufacture of heavy guns, took place on Thursday, between 12 and 1 o'clock, at the Fort Pitt Works.  A gun with calibre of 20 inches diameter, was cast on the Rodman principle, in some 22 minutes from the time of tapping the furnaces.."

Some 170,000 pounds (85 tons) of metal was used and the metal was melted in three furnaces and simultaneously tapped.  It is 20 feet 4 inches long and has a maximum diameter of 5 feet 3 inches.  It is estimated the the shot fired from it will be a half ton sphere or a 750-pound shell with a powder charge estimated at between 80-100 pounds.

A Big One.  --Old Secesh