For the composition of the flammable material used in a carcass, 18th century philosopher
Christian Wolff prescribed 10 parts of pounded
gunpowder, 2 of
nitre, 1 of
sulfur, and 1 of
colophony; or 6 of gunpowder, 4 of nitre, 4 of sulfur, 1 of beaten glass, 0.5 of
antimony 0.5 of
camphor, 1 of
sal ammoniac, and 0.25 of common
salt. For the shell, he started with two iron rings (others used plates), fitting one at one extreme, near the aperture at which the carcass was to be fired, and the other at the other. These he braced with cords drawn lengthwise; and across these, at right angles, laced other cords, making a knot at each intersection. Between the folds of the cords, he made holes, inserted copper tubes, and filled them half full of powder and lead bullets, packing it in with a tow. The internal shell's aperture was then plugged up, and it was immersed in a mixture of 4 parts of melted
pitch, 20 of
rosin, 1 of
oil of turpentine, and as much ground gunpowder as was needed to reduce it to the consistency of a paste. After immersion, the shell was to be covered with
tow, and immersed again, until it was the proper size for the mortar. Carcass shells as used by the Royal Navy from the 18th to the 19th centuries were filled with a mixture of
saltpeter, sulfur, rosin,
sulfide of antimony,
tallow and
turpentine. ==See also==