TRACT 34 .
IN GUNNERY.
9
72. Tuesday, August 10, 1784-; from 12 till 2.The weather thick and cloudy.
N°
Weight of
Vibration of
Point'
struck
| Plugs
Values of
ball
wad
gun
pend
p
S
n
oz
dr
oz
dr
inches
in
lbs
inches
1
56
2
56
3
it
2 i
203
170
89*4
7
674*8
76-62
40-26'
4
14
3
195
159
S9-S
8
676-1
76-64
40-26
5
14
2P
4
12
214
161
89*5
5
677-3
76-67
40-26
6
14
3 i
4
10
215
163
89-3
6
678-6
76-69
40-26
7
14
4
2
5
208
171
89*3
6
679-9
76-72
40-26
8
14
2-f
2
4
208
171
89*1
6
681-1
76-75
40-25
9
13
1
2
10
208
176
89-5
5
682-4
76-77
40-25
10
14
4
10
230
187
90-3
8
683-7
76-80
40-25
11
14
4
12
232
218
90*8
7
685-0
76-82
40-25
N os 1 and 2 were with 4- oz of powder ; all the rest 6 oz.
The mean diameter of the ball was 1*875 ; so that thewindage was *15.
The mean height of the charge of powder was 4*4.
The Gun n°- 3 ; its weight 917 lb.
The object this day was the effect of windage with lowballs, and the effect of wads, both high and low ones. Thewads struck variously, either above, or below or with theball, 'fhe two wads in the last round were made of well-twisted twine, and firmly bound : they struck the pendulumvery hard blows. The other wads were of junk, and didnot strike so hard.
Here, the balls being smaller, and consequently the wind-age more, the vibrations are much smaller, though wadswere used. So that it seems the wads do not prevent theescape of the inflamed powder by the windage, nor makeany sensible alteration in the velocity of the ball.
The velocities are not computed, for the same reason asspecified in the last day’s experiments.
73. The Pendulum block had not been altered since thelast day’s experiments. But the iron stays of the stem had