Chlorophyll an

Green crystalline substance obtained in chlorides, common salt, sodium chloride, being its most imporby evaporating the alcoholic solution of green leaves. tant compound. It is isolated by decomposing hydrochloric acid with manganese dioxide. It may be made by heating salt, manganese dioxide and sulphuric acid. It is a greenish-yellow gas, of a suffocating odor and with great affinity for many of the elements. Water di olves 2 vols. at 15.5° C. It is liquefied by pre ure of 3.66 Atm., 0° C.; the liquid is yellow to orange, sp. gr. 1.47. It is solidified at -102° C. It is manufactured in large quantities for the preparation of bleaching powder, CaOCl2+H2O, which contains up to 43 per cent available chlo- rine. In this form it can be conveniently transported. It is used in the manufacture of certain aniline dyes, in that of can withdraw and live an amœboid life. Choate, RuFUS, LL.D., 1799-1859. M.C. 1831-34; U. S. Senator from Ma . 1841-45. One of the fore- most orators and lawyers of his time. Works , 1862. by Sobieski, Nov. 11, 1673, and by the Ru ians April 30 and Choczim. In s. Ru ia. Here the Turks were defeated July 13, 1769. graver and painter. Chodowiecki, DANIEL NIKOLAUS, 1726-1801. German en- epic on the Persian war. (2) Versifier who lauded Alexander. Chœrilus. (1) Greek poet, ab. 450 B.C., author of a lost Choice. Determination of the will; selection between alternatives; fundamental condition of freedom. See VOLITION. Choir. Singers in church, or portion of the building as- signed to them, properly part of the chancel; in some Protes- tant communions, the organ loft. In architecture, that part of a cathedral or other important church behind the transepts, celebrated. separated by them from the nave, in which the ma was 1785. French diplomatist, Minister 1757-70. Choiseul et Amboise, ETIENNE FRANÇOIS, DUC DE, 1719- Geneva. Convolvulaceæ oriental is , 1834-41. Choisy, JACQUES DENYS, 1799-1859. Prof. of Botany in Choke Berry. Pyrus arbutifolia . Shrub of the Rose America. family bearing small red or black fruits, native of e. N. IMG:content-0866.png:[graphic] that the exciting cause is a micro-organism, the Comma bacil lus , which swarms in the stools of choleraics. Its entrance into the system by the mouth will probably establish a well-marked case of the disease: drinking water is the commonest vehicle for its transportation. It seems probable that the fresh evacuations are not very dangerous, and that they become so only after the occurrence of some unknown putrefactive changes, which are favored by heat and moisture, and but little affected by cold. It is also po ible that the dried bacilli or their spores may be scattered by the wind, as some cases are on record in which infection could not have occurred in any other way. The clothing and all objects which have been in contact with a patient are also dangerous, as from them the germs may gain entrance into the food or drinking water. Although one of the most fatal of the epidemic diseases, its di emination by practically a single agent renders it the easiest to control among rational people. The mortality among attendants upon choleraics is very much le than among those not in direct contact with the disease, and simply for the reason that those thus exposed observe proper precautions in regard to their food, drinking water, etc. The chances are largely against the contraction of the disease by a well person when the food is sound, fresh, and properly cooked, the drinking water boiled or distilled shortly before using, and all articles of diet avoided which may give give rise to indigestion or diarrhea, which favor the development of the bacillus. When the develop me water supply of a community becomes infected the danger is great, and continues until it is purified. This was exemplified during the last epidemic in Italy, where numerous wells became polluted and formed centers of infection to such an extent that many believed them to have been intentionally poisoned. All acids are hostile to the bacilli, and one of the best precautionary measures for the exposed is the use of small doses of the mineral acids several times a day. As might be expected, the mortality is greatest among the ignorant and those forced to live under bad hygienic conditions. In every epidemic there occur many cases of diarrhea, termed cholerine, which often prove fatal, or when neglected run into cholera. To prevent the spread of the disease, all affected with it and those who have been in contact with them should be isolated for three weeks, the vomit and stools disinfected, as well as the clothes, bedding, etc., the general sanitary condition of the community attended to, the use of well water discontinued when po ible, public water-closets avoided, as also contact with the sick and their attendants; and, if po ible, the infected district should be abandoned, until the subsidence of the epidemic, in favor of one more elevated. Treatment consists largely in the use of opium and the mineral acids. In India the most commonly employed remedy is CHLORODYNE (q.v.). It is suggested that inoculations of cultures of the Comma bacillus would prove effectual, and some experiments in that direction have been made, but the data are insufficient to allow of any decided statement. See COMMA BACILLUS.