GUNNERY. 
elevation, but with various charges of powder, 
the greatest charge being the whole weight 
of the ball in powder, and the least not less 
than the fifth part of that weight; then, if 
the elevation be not less than eight or teii 
degrees, it will be found that some ranges 
with the least charge, will exceed some of 
those with the greatest. 8. If two pieces 
of cannon of the same bore, but of diffe- 
rent lengths, are successively fired at the 
same elevation, with the same charge of 
powder, then it will frequently happen 
that some of the ranges with the shorter 
piece will exceed some of those with the 
longer. 9. Whatever operations are per- 
formed with artillery, the least charges of 
powder with which they can be effected, 
are always to be preferred. 10. No field- 
piece ought at any time to be loaded with 
more than one-sixth, or at most one-fifth of 
the weight ot its bullet in powder, nor 
should the charge of any battering-piece 
e’xceed one-third of the weight of its bul- 
let. 
TABLE I. For Horizontal Projections. Fig. 10. 
Given. 
Required. 
Proportions. 
AM, Am 
t AH 
Hu 
2 A M : A m : : R : S. 2 angle t 
A HR:T.anglet AH:;— : 
4 
Hv 
AM, f A H 
A m 
R : S. 2 angle t A H : : 2 A M : 
A m. 
Am, 1 4 H 
A M 
S. 2 angle f A H :R: : AM 
AM, Hu 
A m 
Am 
^ ANxN M=— ,oriLog. 
A N x j Log. N M = Log. \Am- 
Am, Hv 
t AH 
AM 
A m „ „ 
— : Hu : : R ; T. angle (AH. 
AN : Am.:A^ ;NM ndAN 
4 4 7 
XNM = AM. 
Hu, f AH 
A m 
T. angle* AH:R::Ho:— 
4 
t A H, Am 
and any other angle. 
any other amplitude. 
any other amplitude be- 
longing to that angle, 
any other angle belong- 
ing to that amplitude. 
S. 2 angle t A H : S, 2 any other 
angle : : A m : amplitude requir- 
ed. 
A m : any other amplitude : : S. 
2 angle ( AH;S. 2 angle requir- 
ed. 
t A H, H u. 
any other angle. 
any other altitude. 
any other altitude. 
any other angle. 
V. S. 2 angle t A H : V. S. 2 any 
other angle : : H u : altitude re- 
quired. 
H u : any other altitude : : V. S. 2. 
angle t A H : V. S. 2 angle re- 
quired. 
