8. Such is, in few words, the law which presides at the formation of all natural bodies. The innumerable variety of these bodies is the result of a very small number of elementary principles combined in different proportions.
Thus oxygen, combined in certain proportions with sulfur, carbon, and phosphorus, forms carbonic, sulfuric, and phosphoric acids. Oxygen and iron form the oxide of iron, or rust; oxygen and lead, both inoffensive, give place to the oxides of lead, such as litharge, white lead, and red lead, which are poisonous. Oxygen, with metals called calcium, sodium, potassium, forms limestone, soda, and potassium. Limestone, united with carbonic acid, forms the carbonites of limestone, or calcareous stones, such as marble, chalk, building stones, the stalactites of grottos. United with sulfuric acid, it forms the sulfate of limestone, or plaster and alabaster; with phosphoric acid, the phosphate of limestone. The solid base of bones, hydrogen, and chlorine form hydrochloric acid. Hydrochloric acid and soda form the hydrochloride of soda, or marine salt.