 The rectangular casemate was pierced with eight narrow gun ports , one each at the bow and stern and three along each side . Each gun port was protected by an armored <unk> made of two layers of iron riveted together and allowed the guns to elevate only to a maximum of + 5 to + 7 ° . Atlanta was armed with single @-@ banded , 7 @-@ inch ( 178 mm ) Brooke rifles on <unk> mounts at the bow and stern . The middle gun port on each side was occupied by a single @-@ banded , 6 @.@ 4 @-@ inch ( 163 mm ) Brooke rifle . The 17 @-@ caliber , seven @-@ inch guns weighed about 15 @,@ 000 pounds ( 6 @,@ 800 kg ) and fired 80 @-@ pound ( 36 kg ) armor @-@ piercing " bolts " and 110 @-@ pound ( 50 kg ) explosive shells . The equivalent statistics for the 18 @.@ 5 @-@ caliber , 6 @.@ 4 @-@ inch gun were 9 @,@ 110 pounds ( 4 @,@ 130 kg ) with 80 @-@ pound bolts and 64 @-@ pound ( 29 kg ) shells . Atlanta was also armed with a 20 @-@ foot ( 6 @.@ 1 m ) , solid iron , ram that was reinforced by a series of vertical steel bars . In front of the ram was a spar torpedo that carried 50 pounds ( 23 kg ) of black powder on a wooden pole connected to an iron lever that could be raised or lowered by means of <unk> . 
