Chaplet. In heraldry, is always composed of four roses, the other parts being leaves.
Chappe (Fr.). A barrel containing another barrel, which holds gunpowder. It likewise means a composition of earth, horse-dung, and wad, that covers the mouth of a cannon or mortar.
Chapultepec. A strong fortress of Mexico, situated about 2 miles southwest of the metropolis. It consists of an eminence rising to the height of about 150 feet, with a strong castle on top. During the Mexican war it was deemed necessary by Gen. Scott, for strategic reasons, to capture this last outward defense of the capital prior to the attack on the city itself. This was gallantly effected on September 13, 1847, and next day the city was entered by the American forces, thus virtually ending the war. Preparations for the assault were commenced on the night of September 11, and before the evening of the 12th, owing to the skillful arrangement of Gen. Scott’s artillery, the exterior defenses began to give way. Next day was determined on for the attack. The American forces were so placed that the assault could be made simultaneously from different sides at a preconcerted signal, which would be the temporary cessation of the cannonade from their batteries. It was given, and the attacking forces advanced, Gen. Quitman’s division from the south, and Gen. Pillow from the wooded slope on the west, Gen. Smith’s brigade supporting Quitman, Pillow supported by the division of Gen. Worth, and the batteries throwing shells into the fort over the heads of their friends. Under a heavy fire of musketry the attacking forces advance, and step by step they gain every disputed point, scaling-ladders are brought into requisition, an entrance effected, and the defeated Mexicans, dislodged and retreating, are pursued to the very gates of their capital. The American loss during the three days was 833 killed and wounded.
Charcoal. One of the ingredients of gunpowder. It is made by distilling small sticks of wood in closed retorts. Willow, alder, poplar, and dogwood are some of the woods used. In distilling the heat should be kept below redness. Charcoal should be light in weight, and have a velvety fracture. It inflames at about 460° Fahr. Its composition and properties vary with the nature of the wood and mode of distillation employed.
Charcoal obtained from light wood is the best for gunpowder, as it is more combustible and easy to pulverize, and contains less earthy matters. Willow and poplar are used for this purpose in the United States and black elder in Europe. The wood must be sound and should not be more than 3 or 4 years old, and about 1 inch in diameter; branches larger than this should be split up. It is cut in the spring when the sap runs freely, and is immediately stripped of its bark. The smaller branches are used for fine sporting powder.
The operation of charring may be performed in pits, but the method now almost universally used in making charcoal for gunpowder is that of distillation. For this purpose the wood is placed in an iron vessel, generally of a cylindrical form, to which a cover is luted; an opening with a pipe is made to conduct off the gaseous products, and the wood is thus exposed to the heat of a furnace. The progress of distillation is judged of by the color of the flame and smoke, and sometimes by test-sticks, which are introduced through tubes prepared for the purpose.
Properties.—The charcoal thus obtained should retain a certain degree of elasticity, and should have a brown color, the wood not being entirely decomposed. As it readily absorbs one-twentieth of its weight of moisture, which diminishes its inflammability, it should be made only in proportion as it is required for use. Wood generally contains 52 per cent. of carbon, but distillation furnishes not more than 30 to 40 per cent. of charcoal.
As it is desirable to have charcoal for gunpowder very combustible, it must be prepared at a low temperature, and must be light.
Accidents.—When recently prepared charcoal is pulverized and laid in heaps, it is liable to absorb oxygen with such rapidity as to cause spontaneous combustion. This has been the cause of serious accidents at powder-mills, and hence it is important not to pulverize charcoal until it has been exposed to the air for several days. When charcoal has not absorbed moisture, and is mixed with oxidizing substances, it may be inflamed by violent shocks or by friction. This is the principal cause of the accidents which occur in the preparation of explosive mixtures which contain charcoal. See [Gunpowder].
Chard. A town of England, in Somersetshire. Here the royalists were defeated in the civil wars between Charles I. and the Parliament.