POINDEXTER 285 POISON GAS World War, and his aggressive policies, following the outbreak of the war did much to enable France to meet the many crises of the great struggle. President Poincare was a frequent visitor in the war area and his presence did much to encourage and harden the French soldiers. He was succeeded as President in January, 1920, by Paul Deschanel {q. V.) who was, however, obliged to resign on account of illness, and was succeeded by Alexandre Millerand, on September 16, 1920. M. Poincare published several studies in literature and politics, includ- RAYMOND POINCAItt} ing "How France is Governed" (1913). Following his resignation he became leader of the opposition, altho'i^h he heartily supported the government in negotations in 1920 and 1921 following the attempted settlement of economic and political conditions in Europe. POINDEXTER, MILES, United States Senator from Washington. Born at Memphis, Tenn., in 1868, and educated at Washington and Lee tJniversity, he moved to the State of Washington in 1891, where he took up the practice of law. After serving as district attorney, and later judge of Spokane co., he was elected to the National House of Repre- sentatives as a Republican in 1909, and at the expiration of his term was chosen United States Senator. He received the support of the Republicans in the State of Washington as a candidate for the presidential nomination in 1920. Vol. VII— Cyo POINSETTIA, a genus of Euphorbi- acex, now merged in Euphorbia itself. P. pulcherriiiia is a highly ornamental stove plant, with rose-like whorls of bracts. POINT, 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 sup- posed to be moved in any way, it will bf its motion describe a line. POISON. Professor Christison di- vides 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, con- vulsions, etc. A narcotic poison pro- duces stupor, numbness, drowsiness, cold- ness, and stiffness of the extremities, etc.; a narcotico-acrid poison produces a certain combination of the symptoms attendant on both the former classea. Savages poison their arrows with the milky juice ol 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 nearly as they do on animals, that is, they are absorbed into the different parts of a |)lant, destroying the structure. _ Vege- table poisons, especially those which de- stroy animals by action on their nervous system, also cause the death of plants. POISON GAS, USE IN WARFARE. The employment of poisonous or suffo- cating gases in warfare dates back to early times, the use of "stink pots" con- taining burning sulphur and similar materials producing noxious fumes being common among the ancients. It re- mained, however, for the World War of 1914-1918 to bring the practice to a high state of development. The use of such gases in warfare was forbidden by the Hague Convention of 1899, but poi- son gases were introduced by the Ger- mans early in 1915, and their use was afterward adopted by the armies of the Allies. Many different compounds were employed, and substances, which had previously been considered as of aca- demic interest only, were manufactured in vast quantities. The gases were pro- jected by two different methods; by the 19