Mortar shells from this battery plummeted down in high soaring arcs upon the warships, tearing through the canvas sails and bursting upon the wooden deck.
This mortar battery, joined with heavy guns on both sides of the River, made running the blockade a hazardous assignment for British sailing vessels.
It is believed this battery was used for mortars and consisted of four land mortars, a 13" brass, a 10" iron, a 10" brass and an 8" iron as well as one 13" iron sea mortar. Shells could be hurled accurately 1,200 to 1,500 yards - enough to provide a firing field reaching completely across to the opposite river bank.
These mortars fired over parapets walls. No frontal ditches at this battery were necessary due to the virtually insurmountable cliffs on the east.
Firing Methods & Projectiles
Mortars were fired at an upward angle of 45 to 70 and were capable of hurling several different types of shells. Hollow balls filled with powder would explode on impact spreading fragments in all directions.
Incendiary shells, called "carcasses", were loaded with pitch or other combustible materials to spread fire when striking a target. Other projectiles, called "baskets" or "canisters", were filled with stones. All of these explosive and incendiary projectiles were called "boms."
Mortar crews were smaller than those manning cannons but the firing procedure was basically the same - sponging, loading, aiming and firing. However, as with all muzzle-loading pieces, crew teamwork, rhythm and weeks of practice were required.