THE ROYAL ARTILLERY INSTITUTION. 
239 
APPENDIX. No. 1. 
COPY OF A DRAUGHT OF REPORT OF AN EXPERIMENT AGAINST A SCREEN 
REPRESENTING THE WALL OF A FORTRESS, ACCORDING TO CARNOT'S 
SYSTEM. DATED WOOLWICH, OCTOBER 24, 1822. 
1. The experiment commenced on the 2nd August, 1822, and continued 
till the 24th September following, during which period 1167 rounds of 
ammunition were fired from the following natures of ordnance, viz :— 
Length. Weight, 
ft. cwt. qrs. lbs. 
24-pr., iron. 9 . 48 0 0 
8-in. howitzer, iron ... 4 . 20 2 2 
68-pr. carronade . 5 . 36 0 0 
10-in. howitzer, iron... 5 . 39 2 20 
8-in. mortar, iron . 8 1 0 
These pieces were each fired at ranges of 400 and 500 yds. distance from 
the crest of the counterguard in front of the wall. 
2. The following is a statement of effect of the total number of 1167 
rounds fired:— 
Rounds. 
Grazed short. 417 
Took effect on wall . 377 Rather less than one third. 
Went over wall. 373 
Total 1167 
Of the number of 377 rounds that took effect on the wall 116 rounds 
struck the wall at or below 12 ft, from the top, being only one-tenth of the 
number of rounds fired; but in stating this unfavourable result, it is necessary 
to observe that every allowance is to be made for loss of effect, by frequent 
change of the pieces of ordnance used, as well as alteration in the charges, 
elevations, and stations they were fired from, particularly in the commence¬ 
ment of a difficult operation, when many of the rounds were thrown away in 
experiments as to the best charges. 
3. Por the purpose therefore of forming a just opinion of the effect of 
this experiment, it is requisite to take it into consideration, in three points of 
view, as follows :— 
(1) The individual effect of each piece of ordnance. 
(2) A comparison of effect from 400 yds., and from 500 yds. 
(3) With regard to the best angle of elevation to be used. 
[vol. III.J 
p 
