CHEMISTRY.
[1.] Transcriber’s Note: This note was omitted in the original. Wikipedia has to say: “In general in ancient Greece, each state, city or village possessed its own central hearth and sacred fire, representing the unity and vitality of the community. The fire was kept alight continuously, tended by the king or members of his family. The building in which this fire was kept was the Prytaneum, and the chieftain (the king or prytanis) probably made it his residence.”
[2.] “Lavoisier,” läˈvwäˈze-āˌ. See Appleton’s “Chemistry,” pages 19, 21 and 118. He was condemned to death by a revolutionary tribunal at Paris on a frivolous charge brought against him as one of the farmers of the taxes during the Reign of Terror.
[3.] “Phlogiston,” flo-jisˈton. Stahl supposed it to be pure fire, fixed in combustible bodies in order to distinguish it from fire in a state of liberty.
[4.] “Magnesium.” A shining, almost silver-white metal. When heated it may be rolled out into very thin, long strips resembling ribbons, which will burn with an intense light. In burning it produces magnesium oxide or magnesia, which falls as a fine white powder.
[5.] “Dr. Priestly.” See “Chemistry,” page 118. (1733-1804.) An eminent English divine and philosopher. His partiality to the French Revolution excited the English against him, and in one of the riots his home, library and manuscripts were destroyed by the fire kindled by an angry mob. His later home was in Northumberland, Pa. He wrote between seventy and eighty volumes on history, literature, theology and science.
[6.] In a few volcanic districts steam escapes from the earth, which contains small quantities of boric acid. These vapors are condensed into water, which is again evaporated and the acid crystallized out. When this acid is mixed with alcohol and the solution set on fire it burns with a green flame. See “Chemistry,” page 157.
[7.] “Corpuscles of the blood.” Minute particles, both red and white, existing in the blood, which can be seen under a microscope. In the human species the red corpuscles are thick and circular. They are so small that Young says it would take 255,000 of them to cover a surface of a square inch. They are elastic and pliant, so that they can pass through blood vessels having a smaller diameter than themselves. The white corpuscles are more globular than the red, and contain more fat, and have the power of changing their form. These spontaneous changes have been thought by some scientists a proof that they are microscopic animals. But this is scarcely a sufficient reason for admitting that they are animalculæ, as the muscles of a body, when separated from it, often manifest apparently spontaneous movements.
[8.] Phosphoric acid is always produced by burning phosphorus in air or oxygen. The experiment may be performed as follows, but before undertaking it see page 167 of the “Chemistry,” and note with how much care it must be handled: Place a fragment of carefully dried phosphorus in a small cup on a stand in the middle of a large plate, ignite it by a hot wire, and place over it a bell-glass. White fumes will fill the glass and aggregate into small particles, which will fall to the plate, presenting the appearance of a miniature snow storm.