THE ROYAL ARTILLERY INSTITUTION. 
181 
Table I. 
Practice at Shoeburyness on 15th March, 1861, with shot from a 40-pr. Armstrong 
rifled gun, giving right-handed rotation; weight of piece 31 cwt., charge 5 lbs. 
Pive rounds fired at each elevation; no allowance for deflection in“ laying.” 
Elevation. 
Mean 
range. 
Mean deflection. 
Right. 
Left, 
O 
yds. 
yds. 
_ 
2 
1061 
•06 
— 
3 
1421 
1*0 
— 
4 
1769 
3-6 
— 
5 
2113 
6*2 
— 
7 
2687 
16-4 
— 
The above are fair average deflections and have not been chosen as being 
favourable to the statement—that right-handed rotation gives right deflection 
to projectiles with pointed or round heads. It is found as may be seen from 
this table and from others further on, that with this gun the derivation is 
hardly sensible at 1000 yds., and also that at this range a wind blowing 
across the line of fire from right to left may not only counteract the derivation 
but even deflect the shot to the left; as however the range increases the right 
deflections become very apparent. 
Table II. 
Practice at Shoeburyness on 9th April, 1862, with shot weighing about 60 lbs., 
from a 32-pr. gun rifled on a French principle, and giving left-handed rotation; 
charge, 5 - 5 lbs. Fifteen rounds fired at each elevation; no allowance for 
deflection in “ laying.” 
Elevation. 
Mean 
range. 
Mean deflection. 
Right. 
Left. 
o 
yds. 
yds. * 
yds. 
2 
821 
—i 
1*5 
5 
1672 
— 
6*1 
10 
2891 
— 
19-8 
Of the 15 shot fired at 2°, two deflected to the right, one had no deflec¬ 
tion, and the remaining eleven deflected to the left. All the shot fired 
at 5° and 10° deflected to the left, the deflection increasing with the angle of 
elevation. 
