BALLS, LIGHT.
Light Balls are thrown from mortars at night, to discover the operations of the enemy’s working parties, &c.
Light balls burn from 10 to 20 minutes.
BALLS, SMOKE.
Smoke balls are fired from mortars to suffocate the men in mines, &c., or to prevent them continuing their work. They are also used to conceal manœuvres, &c., from an enemy.
Smoke balls burn from 25 to 30 minutes.
To construct hollow Globes, or Cases for Light Balls, &c.
The canvas, or paper, may be formed in the following manner, viz.:—With radius of half the intended calibre, describe the circleA B C D(videFigure 20, Practical Geometry), and divide the same into four equal parts. FromBwith radiusA Bdescribe arcA E, fromAwith radiusA Bdescribe arcB E, and fromEwith radiusE Adescribe arcA B. Eight pieces, asE A B, will form a ball nearly, the edges being brought close together.
CARCASSES.
Carcasses, a species of shell, are filled with composition, the flame from which is extremely powerful, and nearly unextinguishable.They are much used in bombardments of towns, setting fire to shipping, &c., and are discharged from guns, mortars, and howitzers, similarly to common shells; from which, however, they differ, in being made thicker, to enable them to withstand the intensity of fire; and in having three fuze holes instead of one.
Carcasses burn from 8 to 10 minutes.
Common shells may be made to produce effects similar to carcasses, by filling them with a proportion of Valenciennes composition, and bursting powder.
All carcasses have three holes; and, from guns and howitzers, are fired with sabots.