The Mount Pleasant Battery was a two-gun battery built at the end of present-day Schweers Lane, adjacent to Pitt Street. It was armed with two 10-inch seacoast mortars. From this vantage point, the battery could fire on the three Federal fortifications at the time, which included Fort Moultrie, Castle Pinckney, and Fort Sumter.
The Mount Pleasant Battery, commanded by Captain Robert Martin, almost started the war early after firing practice shots in the direction of Fort Sumter in early April 1861. Martin was drilling his men and several shells exploded so close to Fort Sumter that shrapnel hit the walls. On April 6, Anderson sent a dispatch to Brigadier General P. G. T. Beauregard noting, “ I deem it my duty to call your attention to the fact that some of the shells fired this morning from the mortar battery at Mount Pleasant have exploded so near this work as to render the further firing dangerous to the occupants of this fort, unless the direction of the mortar is changed.” Beauregard responded the next day expressing his regret over the incident and stating that the officer of the battery had been notified to re-direct his practice shells.
The Mount Pleasant Battery participated in the firing on Fort Sumter, April 12 & 13, 1861. Afterwards, when Captain Martin submitted his report to Beauregard, he stated:
Probably you will see I fired faster than ordered. Captain Ferguson can inform you that Colonel Ripley allowed me to fire faster. The officers and men are in good condition, though much mortified at not being noticed by Major Anderson. [Anderson did not return fire on the Mount Pleasant Battery] After the forty-eighth shot the fort was seen to be on fire, and the excitement was so great no account was kept of the shots. I think we fired about ten shells more.
Actually, when the final report was filed after inventory, the Mount Pleasant Battery fired a total of eighty-one shells on Fort Sumter in the two-day attack.
The Mount Pleasant Battery was later rebuilt as Battery Gary.