Page:The New International Encyclopædia 1st ed. v. 04.djvu/775

CHLOROFORM. 677 CHXOROPHYCE^. acetone; the crude product of distillation is puri- fied by shaking with strong sulphuric acid and redistilling. To be fit for use as an ana-sthetic, chloroform must be perfectly pure; and as by the action of light it is readily decomposed if kept in contact with moist air, bottles containing chloroform should lie well stoppered and kept in the dark. Pure chloroform is not darkened by shaking with sulphuric acid; it should also con- tain no phosgene gas, which forms by the action of moist air on chloroform, and may cause bad after-effects when the latter is employed as an anaesthetic. To prevent the formation of phos- gene gas a small amount of alcohol is added to chloroform. The presence of chloroform in sub- stances submitted for examination may be readily detected by the so-called carbylamine reaction: a small quantity of the substance is gently warmed with a mixture of aniline and an alco- holic solution of caustic potash, when, if chloro- form was present, an intensely nauseous smell is observed, due to the formation of carbylamine (phenyl isocyanide). Preparations of chloro- form are often used to mask the taste of nau- seous medicine. The chances of danger from using chloroform as an ansesthetic are very small; statistics show that no more than one death occurs in 3000 cases of administration of the substance. Ether, however, is even safer, and is in this country preferred to chloroform. If inhaled in small quantities, chloroform has the effect of abolishing the sensation of pain; for this purpose it is successfully employed in labor. It may also be inhaled to relax spasms in cases of tetanus, etc. As an anesthetic, chloroform should be administered with the greatest caution, and ether is substituted for it if the patient suf- fers from heart disease. If ana>sthesia be pro- longed several hours, three stages may be dis- tinguished: At first the highest functions of the organism are affected; confusion of the mind is accompanied in the patient by a pleasurable feeling throughout the body; general sensation is blunted, while the lower motor functions are powerfully excited, and the arms and legs are tossed about in a disorderly manner. This is followed (second stage) by general depression, and soon genera] ana'sthesia sets in. The ad- ministration of chloroform is, however, carried on until the patient is partially narcotized and reflex excitability is completely abolished (third stage). During the administration of chloro- form, vomiting is very liable to occur. If dan- gerous symptoms appear, artificial respiration should at once be resorted to, brandy injected subcutaneously, and the patient's lower extremi- ties elevated. Chloroform was discovered by Liebig and Soubeiran in 1831; its ana-sthetic properties were first observed by Simpson, of Edinburgh, in 1S48. CHLOrROPHANE (fromGk. xXupis, chloros, greenish -vclluu -r <t>a.liitiv, phainein, to appear). A variet}' of lluorite or fluorspar which emits a bright emerald-green light on a comparatively low rise of temperature, in consequence of which it has some value as a gem-stone. Excellent specimens of this mineral are found in Trumbull, Conn., and also Amelia Courthouse, Va. CHLOROPHY'CE.a: (Neo-Lat. nom. pi., from Gk. x^"f"k, rhlOrus. greenish-yellow + (Jiimf, phi/los, seaweed). One of four great groups of algse, and commonly called the green algse. It comprises a large and diverse assemblage of orders and families, partly described in the arti- cle Aui.E (q.v.). The color of the cells is gen- erally clear green, due to chlorophyll which is not masked by the presence of other pigment.s. as in the red, brown, and blue-green algse. The CHLOBOPHYCEX. 1, Scenedeemna (a), and its division (6); 2, Ulotbrix, Bhovr. ing escaping spores (a), a resting spore (b), and it« germi- nation (e); 3, Cblorospbara, showing resting stage (a), and formation of spores (6) ; 4, Stigeoeloniam. types of Chlorophycen; range from one-celled forms to those as conspicuous as the sea-lettuce (Ulva) and stoneworts (Charales). The lower groups generally live in water, where they form sediment in the bottom of ponds and ditches, or slimy coatings on the surfaces of water plants or other objects. Certain groups are free-swim CHLOROPHYCE.E. 1, Uotrydiiim (a), showing formation of gametes (b), their fusion (c), and a young plant (rf): 2, Vaiicheria, showing 8ex-orgau8 (a) formation of large epore (b), its escape (c), and germination (d) ; 3, Br.yopsis. ming. the cells being provided with cilia. ^Many of the simpler forms live in the air, on bark of trees, on stonework, and in other moist and shaded situations. The green growth, pleurococcus, on the north side of trees, is ii familiar example. Among the unicellular forms the desmids are the most conspicuous and beautiful, comprising