Point

Collier's New Encyclopedia (1921)

2026 Editor's Note: This page uses language about other peoples, religions, or nationalities that was commonplace when the book was published and is offensive by today's standards. The text has been left exactly as it was printed, rather than cut or softened, so that the historical record — including how ordinary such language once was — is preserved. (Ed: ET 2026-07-22) in geometry, a quantity which has no parts, or which is indivisible, or which has position without magnitude. Points may be regarded as the ends or extremities of lines. If a point is supposed to be moved in any way, it will by its motion describe a line. POISON. Professor Christison divides poisons into three great classes: Irritants, narcotics, and narcotico-acrids, or narcotico-irritants. A fourth class is sometimes added, septics, consisting of animal poisons, such as the bites of rabid animals and venomous snakes, the stings of insects, and the poison generated by pestilential carbuncle, etc. An irritant poison produces violent pain and cramp in the stomach, nausea, vomiting, convulsions, etc. A narcotic poison produces stupor, numbness, drowsiness, coldness, and stiffness of the extremities, etc.; a narcotico-acrid poison produces a certain combination of the symptoms attendant on both the former classes. Savages poison their arrows with the milky juice of various Euphorbias or of the manchineel, or by the juice of two species of Strychnos. Both in man and in the inferior animals there is often a curious correlation between the color of the skin and hair ard immunity from the action of certain vegetable poisons. Metallic poisons act on vegetables vegetab nea nearly as they do on animals, that is, they are absorbed into the different parts of a plant, destroying the structure. Vegetable poisons, especially those which destroy animals by action on their nervous system, also cause the death of plants.