9. TERREPLEIN, EAST ANGLE. From this point a good view may be obtained of the shore of Tybee Island, from which the fort was bombarded. The two batteries containing the 10 James and Parrott rifled guns, which did the principal damage to the fort, were located on the western point of Tybee just north of the present highway bridge. The 9 other batteries of mortars and siege guns were at various places along the shore for 2 miles in the direction of the lighthouse. The small brick lighthouse on Cockspur Point was built about 1840 and therefore was a feature of the landscape at the time of the bombardment. 10. THE PRISON. From October 23, 1864, to March 4, 1865, the northeast, southeast, and part of the south casemates of Fort Pulaski were used as a military prison. 11. THE BREACH. In three casemates at the southeast angle there are solid brick walls without embrasures. These walls were constructed in 1862, after the surrender, by troops of the 48th New York Volunteers to close the breach, or opening, made by the Federal shot and shell during the bombardment. 12. THE SOUTHWEST BASTION. The interior of the southwest bastion was destroyed by fire in 1893. This part of the fort has been left unrestored to show details of the foundation construction. All arches are completed beneath the floor level and are laid on a platform of yellow pine timbers, called grillage. The grillage in turn is supported by yellow pine piles which are driven deep into the mud of Cockspur Island. 13. HEADQUARTERS (SURRENDER ROOM). The surrender of Fort Pulaski was executed in the quarters of Col. Charles H. Olmstead, Confederate commander. In 1925 a lightning fire destroyed the officers’ quarters. This room was restored in 1935. 14. CISTERN ROOM. This room, also destroyed in the 1925 fire, has been left unrestored to show construction details. The cylindrical brick structure below floor level is the top of a water cistern. 15. BOTTLE COLLECTION. Nearly 1,000 bottles were found in the Fort Pulaski moat when the mud was cleaned out in 1935. These bottles had been thrown into the moat by workmen building the fort and by Confederate and Union soldiers during the Civil War. A part of the collection is shown in this room. 16. THE MOAT. The wet ditch, or moat, which completely surrounds the main fortification and the demilune, varies in width from 30 to 48 feet. It has an average depth of 7 feet. The water, brought through a canal from the South Channel of the Savannah River, is controlled through a series of tide gates. Fish, crabs, shrimp, oysters, and turtles live in the moat.