For the 24 pounder, the main naval cannon employed by both the British, and America by association, and French. 5.55” diameter, the 24 pounder. 24 pounders were the main guns on the heaviest of frigates through the 17th and 18th centuries, only exceeded by the 36 pounder which required a 14 man crew per gun. Guns were mounted in accordance with the mission which could include objectives at sea or on land. The Constitution during the War of 1812, typically mounted thirty 24 pounders. English first rate ships carried 24 on their middle deck. This classic cannon ball gauge for the 24 pounder recently turned up in Pennsylvania and surely is American as it is unmarked. Iron, pitted overall typical for storage in a waterfront shed or bunker. A very rare naval artillery instrument which could have served on the Constitution or one of her sister ships or possibly through the Revolution.