OF PROJECTILES. 201

196. To form a comparison of the effects that (hot ofdifferent diameters with different initial velocities produce atdifferent distances on a body of troops ; they must beconsidered as a homogenous butt: then the formula StrrDa* 1(183) will give the relative penetrations. The absolutenumber of men that a lhot with a given initial velocity willpass through may be determined by experiment.

The relative penetrations in the following table have beeacalculated on a supposition that from the resistance of the airr—i% in a grlb. shot, in order to compare together thenumber in this and the preceding table (183). The cal-culations are not carried beyond 680 yards, which is consi-dered in field engagements as the greatest distance that shotcan range to, with a certainty of doing execution ; in extra-ordinary cafes indeed, when the nature of the ground andthe position of the enemy are very favourable (192), therange may be extended with tolerable success.

The relative Penetrations of Shot projected from differentDistances with given initial Velocities.

Nature of

Weight of

2 D

At

At

Guns.

Prs .

Powder.

-To

^ >Feet.

° 0

U -£

340yards.

680

yds.

Com- (16

3

1 of

1240

17571

00

00

8509

mon -j 8

2

ni• 2

1265

14625

9360

5743

length. I 4

1

3 i

1283

11840

6754

3479

f 8

2

I 2 C 6

13329

8358

4919

c . 4

1

3 !

1222

10784

5933

2944

Short J 8

1

10s

978

8746

4874

2450

Guns. j 4

—

13 i

978

6896

323°

1271

I 8

without^

icf

675

4110

i 73 8

427

I 4

wads I

- 3 -

675

3241

1024

251

197. To reduce into numbers the relative penetrationsinscribed m the tables (183, 196), make the following orsimilar experiment: with a charge that gives a known initialvelocity, fire a gun against a butt, and measure the penetra-tion of the shot: then place two horses or other cheapanimals close to the same butt, and lay the gun so that thyshot after passing through the most solid parts of their bodies

may