GUNNERY. 
а. That the velocities communicated to balls or fliot, 
of the fame weight, by different “quantities of powder, 
are nearly in the fubduplicate ratio of thofe quantities: 
a fmall variation, in effedt, taking place when the quan¬ 
tities of powder became great. 3. And when (hot of 
different weights are employed, with the fame quantity 
of powder, the velocities communicated to them are 
nearly in the reciprocal fubduplicate ra'tio of their 
weights. 4. So that, univerfally, fliot which are of 
different weights, and impelled by the firing of different 
quantities of powder, acquire velocities which are di- 
redtly as the fquare roots of the quantities of powder, 
and inverfely as the fquare roots of the weights of the 
ffiot, nearly. 5. It would therefore be a great improve¬ 
ment in artillery, to make ufe of ffiot of a long form, or 
off heavier matter; for thus the momentum of a (hot, 
when fired with the fame weight of powder, would be 
increafed in the ratio of the fquare root of the weight 
of the ffiot. 6. It would alfo be an improvement to di- 
miniffi the whidage ; for by fo doing, one-third or more 
of the quantity of powder might be faved. 7. When 
the improvements mentioned in the laft two articles are 
confidered as both taking place, it is evident that about 
half the quantity of powder might be faved,, which is a 
very confiderable objedt. But important as this faving 
may be, it feems to be ftill exceeded by that of the article 
of the guns; for thus a fmall gun may be made to have 
the eftedt and execution of another of two or three times 
its fize in the prefent mode,, by difcharging a ffiot of 
two or three times the weight of its natural ball or round 
ffiot. And thus a fmall fliip might difcharge ffiot as 
heavy as thofe of the greateft now made ufe of. 
“ Finally, as the above experiments exhibit the regu¬ 
lations with regard to the weights of powder and balls, 
when fired from the fam‘e piece of ordnance, &c. fo by 
making fimilar experiments with a gun, varied in its 
length, by cutting oft' from it a certain part before each 
courfe of experiments, the effedfs and general rules for 
the different lengths of guns may be certainly deter¬ 
mined by them. In ftiort, the principles on which thefe 
experiments were made are fo fruitful in confequences, 
that in conjundtion with the effedts refulting from the 
refiftance of the medium, they feem to be fufficient for 
anfwering all the enquiries of the fpeculative philolo- 
p;her, as well as thofe of the pradtical arfilleriff.” 
In 17 86 was publiftied the firft volume of Dr. Hutton’s 
Tradts, in which is detailed, at great length, another 
very extenfive courfe of experiments which were car¬ 
ried on at Woolwich in the years 1783, 1784, ar.d 1785, 
by order of the late duke of Richmond, mafter-general 
of the ordnance. The objedts of this courfe were very 
numerous, but the principal of them were tlie following : 
“ 1. The velocities with which balls are projedted by 
equal charges of powder, from pieces of the fame weight 
and calibre, but of different lengths. 2. The velocities 
with different charges of powder, the weight and length 
of the gun being the fame. 3. The greateft velocity 
due to the different lengths of guns, to be obtained 
by increafing the charge as far as the refiftance of the 
piece is capable of fuftaining. 4. The eft'edf of varying 
the weight of the -piece ; every thing elfe being the 
fame. 5. The penetration of balls into blocks of wood. 
б. The ranges and times of flight of balls; to compare 
them with their initial velocities for determining the re¬ 
fiftance of the medium, 7, The effedt of-.wads ; of-dif¬ 
ferent degrees of ramming ; of different degrees of wind- 
-age ; of diff erent positions of the vent; of chambers, 
and trunnions, and every other circumftance neceffary 
to be known for the improvement of artillery.” 
All thefe objedts were obtained in a very p.erfedt and 
accurate manner ; excepting only the article of ranges, 
which were not quite fo regular and uniform as might 
be wiffied. The balls too were moft of them of one 
pound weight; but the powder was increafed from one 
ounce up till the bore was quite full; and the pendu- 
JU 
him was from 600 to 8oolb, weight. The conclufions 
from the whole were as follow : 
“ 1. That the former law, between the charge and 
velocity of ball, is again confirmed, viz. that the velo¬ 
city is diredfly as the fquare root of the weight of pow¬ 
der, as far as to about the charge of eight ounces : and 
fo it would continue for all charges, were the guns of 
an indefinite length. But as the length of the charge 
is increafed, and bears a more confiderable proportion 
to the length of the bore, the velocity falls the more 
Ihort of that proportion. 
“2. That the velocity of the ball -increafes with the 
charge to a certain point, which is peculiar to each gun, 
where it is greateft ; and that by farther increafing the 
charge, the velocity gradually diminifhes, till the bore 
is quite full of powder. That this charge for the great¬ 
eft velocity is greater as the gun is longer, but not ' 
greater however in fo high a proportion as the length 
of the gun is; fo that the part of the bore filled with 
powder bears a lefs proportion to the whole in the long 
guns, than it does in the Ihort ones; the part of the 
whole which is filled being indeed nearly in the recipro¬ 
cal fubduplicate ratio of the length of the empty part: 
the other circumftances are as in the following Table : 
Gun. 
Num. 
Length of 
the Bore. 
Length 
filled. 
Part ofthe 
Whole. 
Wt. of the 
Powder. 
1 
inches. 
28-2 
inches. 
8-2 
X. 
oz. 
12 
2 
38-1 
9'5 
.X 
14 
3 
57’4 
io- 7 
16 
4 
79*9 
12 * z 
20 
18 
“3. It appears that the velocity continually increafes 
as the gun is longer, though the increafe in velocity is 
but very fmall in refpedt of the increafe in length, the 
velocities being in a ratio fomewhat lefs than that of 
fquare roots of the length of the bore, but fomewhat 
greater than that of the cube roots of the length, and is 
indeed nearly in the middle ratio between the two. 
“4. The range increafes in a much lefs ratio than the 
velocity, and indeed is nearly as the fquare-root of the 
velocity, the gun and elevation being the fame. And 
when this is compared with the property of the veloci¬ 
ty and length of gun in the foregoing- paragraph, we 
perceive that very little is gained in the range by a 
great increafe in the length of the gun, the charge 
being the fame. And indeed the range is nearly as the 
5th root.of the length of the bore; which is fo fmall 
an increafe, as to amount only to about -£th part more 
range for a double length of gun. 
“5. It alfo appears that the titne of the ball’s flight is 
nearly as the range ; the gun and elevation being the 
fame. 
“6. It appears that there is no fenfible difference 
caufed in the velocity or range, by varying the weight 
of the gun, ’nor by the weight of wads, nor by different 
degrees of ramming, nor by firing the charge of pow¬ 
der in different parts of it. 
“ 7. But a great difference in the velocity arifes from 
a fmall degree of windage. Indeed with the ufnal ef- 
tablilhed windage only, namely, about ^th of the ca¬ 
libre, no lefs than between and a of the powder el- 
capes and is loft. And as the balls are often fmaller 
than that fize, it frequently happens that half the pow¬ 
der is loft by unneceffary windage. 
“8. It appears that the refuting force of wood to 
balls fired into it is not conftant. And'that the depths 
penetrated by different velocities or charges are nearly 
as the logarithms of the charges, inftead of being as the 
charges themfelves, or, which is the fame thing, as the 
fquare of the velocity. 
“9, Thefe, and moft other experiments, (how that 
balls are greatly deflected from the direction they are 
4 projected 
