46. Sulphur is a simple combustible substance, of yellow colour, which is found pure, or native, in several parts of the world, and is sufficiently familiar to us under the name of brimstone ([211]). It strongly attracts oxygen ([21]), and is thereby converted into sulphuric acid ([24]). It frequently occurs in combination with mineral substances, such as arsenic, antimony, copper, and other metallic ores.
47. Phosphorus is a combustible substance which, when pure, somewhat resembles bees’-wax both in colour and consistence; and, when exposed to the air under the usual temperature of our atmosphere, is luminous in the dark, and has a smell somewhat resembling that of garlic. It is so combustible that, when melted, it should be kept under water, as it cannot be exposed to the air during this process without great risk of catching fire. This substance is not known in a native state; and the whole of what is used in philosophy and commerce is obtained by different artificial processes. In union with oxygen ([21]) it becomes converted into an acid, called phosphoric acid ([25]), and, under this form, in conjunction with lime, it constitutes the bones of men and animals. The greater part of the phosphorus of the shops is obtained from bones.
48. Carbon is a name given to the pure inflammable part of charcoal. It is abundantly diffused throughout nature, for it enters into the composition of several minerals, and of all vegetable and animal bodies. The purest form under which carbon is known to exist is in the diamond ([50]). It may, however, be obtained sufficiently pure, for all common purposes, by burning a piece of wood, covered with sand, in a vessel called a crucible. In combination with oxygen ([21]) it forms carbonic acid ([26]). Carbon is a chief component part of pit-coal ([217]), petroleum ([213]), and other bituminous substances.
CLASS I.—STONES.
ORDER I.—EARTHY STONES.
I. HARD: those which scratch Glass.