THE EOYAL AETILLEEY INSTITUTION. 
87 
structure advisable, there are no sufficient reasons for incurring great 
additional expense by the general adoption of wholly iron-plated works.* 
wae Oitice, Oct. 1866. W. E. DHUMMOND JEEVOIS. 
A. 
An analysis of the Statements contained in a Confidential "Report by Majot 
D. B. Harris , C.S.A ., with reference to the Bombardment of Fort Sumter , 
Charleston Harbour , by the Monitors and Ironsides , under the command of 
Admiral Dupont , on the 7 th of April, 1863. 
Eort Sumter was a brick casemated work, designed to mount two tiers of 
guns in embrasures, and one tier en barbette; in all, 135 guns. The upper 
tier of embrasures was not finished by the Federal Engineers, and was never 
completed by the Confederates; the spaces left for them were walled up 
with brickwork. At the date of the bombardment the exposed faces (viz. 
the eastern and the north-eastern) mounted 33 guns. 
The fort was bombarded from distances varying from 900 to 15,000 yards 
with the following results, viz.— 
Detailed Table. 
ft; 
Eemaeks; 
15 -inch shells— 
8 shells struck fairly; average penetra¬ 
tion .. . 
2 ; 40 
Two of these shells “destroyed” two embra¬ 
sures, two others dislocated the masonry of 
two piers, and knocked out the arches of 
the embrasures. One shell broke, and stuck 
in the sole of an embrasure; 
1 entered W. Quarters, exploded, da¬ 
maging walls. 
3 scaled, ricocheted, and spent; 
12 total. 
* Eeports have recently reached this country of an experiment made at Fortress Monroe, iii 
America, against a granite wall 36 ft. long, 30 ft. high, and 8 ft. thick,'.covered with four 1-in. plated 
of iron placed one upon another, and fixed by iron bolts passing through the wall. It is stated that 
this structure was destroyed by eleven shots from a 15-inch smooth-bore gun^ and a 12-inch rifled 
gun, at a range of 350 yds. The experience gained in this country would lead us to have antici¬ 
pated this result. The wall, only 8 ft. thick (they are 14 ft. thick in the new English works), was 
not supported by the arches of casemates behind it, which, in the English works, form a large 
portion of the strength of the structure; and the iron plating was so insufficient and so ill- 
arranged as to afford no appreciable aid to the resistance of the mass. If there had been a thin 
plate of iron at the back of the granite, in addition to the plating in front, and the whole had 
been supported either by arches or by struts answering the same purpose, the structure would have 
resisted very well; 
