Page:The American Cyclopædia (1879) Volume II.djvu/564

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544 BENZINE 2,184. Crystal lake, a large body of water, is situated in the W. part. The chief productions in 1870 were 8,906 bushels of wheat, 15,079 of Indian corn, 48,263 of potatoes, 658 tons of hay, and 40,508 Ibs. of maple sugar. Capital, Benzonia. BKZIE, or Benzene, a light oil of petroleum. Mitscherlich in 1833 obtained an oil by the dis- tillation of benzoio acid with an excess of caus- tic lime, to which he applied the name of ben- zine. The same body had been discovered by Faraday in 1825, and named by him bicarbu- retted hydrogen. Liebig, in reprinting Mit- scherlich's article in his Annalen, objected to the termination in, and changed it into ol, and thus introduced the now name benzol. For a long time therefore benzin and benzol were used synonymously by different authors the French adhering to Mitscherlich and calling the substance benzine, while the English called it benzole. After the discovery of petroleum the word benzole or benzine was applied to a liquid of a totally different chemical constitu- tion, though analogous in some of its proper- ties. As soon as it was ascertained by careful chemical analysis that the series of hydrocar- bons derived from petroleum were different from those obtained from coal tar, scientific men and oil refiners began to recognize a distinction between benzole and benzine, and by general agreement the latter word was applied to the light oils of petroleum, while benzole was re- served to designate the original oil discovered by Faraday, and now made in enormous quan- tities from coal tar to be used in the manufac- ture of aniline colors. Commercial benzine is a mixture of various hydrocarbons, and it is impossible to assign a constant composition or chemical formula to the article sold under this name. The following table will exhibit some of the products derived from petroleum : Rhtgoline, specific grav. 0-60 (90"B.). goes over at 100'F. Gasoline, " " 0-68-0-61 (80-90'B.) " " 170 Naphtha, " " 0-67-0-68 (70-SO'B.) " " 280 Benzine, " " 0-78-0-67 (60-70B.) " " 800 Kerosene, " " 0-78-0-72 (50-60B.) " " 400 Above 400 F., mineral sperm and paraffine oil, with specific gravity 72 to 85, are produced. In the United States the petroleum refiners apply the trade name benzine to the naphtha that comes over at 300 F., and has the specific grav- ity of 0-73 to 0-67=60 to 70 Baume. In Eng- land the term "benzene" is sometimes applied to the volatile naphtha obtained in the rectifica- tion of coal tar, and also to petroleum ether. Benzine is a colorless, ethereal liquid, volatile at ordinary temperatures, so that its vapor takes fire at a distance, the same as that of ether; its specific gravity is 0-70; it boils at 140 F. (benzole, 176 F.); it has never been frozen (benzole freezes at 37 F.). It increases the illuminating power of gases, but is inferior to benzole in this respect; it burns with a smoky flame. It does not mix with water or methylic alcohol, but does so readily when warmed with absolute alcohol, fatty and essential oils, and BENZOIC ACID bisulphide of carbon. It dissolves fats, wax, and paraffine ; india rubber swells up and finally goes into solution ; mastic, damar, colophonium, and pitch are with difficulty attacked by it, and amber, copal, and shell lac scarcely at all. If asphaltum or pitch be covered in a test tube with benzole, it is rapidly dissolved into a tarry liquid ; whereas benzine is after the lapse of a few hours scarcely colored by the pitch. Fine benzole can in this way be distinguished from benzine. Benzine is used in the manufacture of varnishes and paints; to remove grease spots; to extract oils and essential principles from seeds and plants; to make water-proof leather ; to carbonize illuminating gas in the manufacture of air gas ; to preserve anatomical specimens; as a substitute for turpentine in paints; in the manufacture of lampblack; and as a highly explosive and dangerous burning fluid. It has been used to adulterate kerosene, and this abuse of the article has cost hundreds of lives. The wholesale price of benzine in the United States in 1870, according to the report of Dr. Chandler to the board of health of the city of New York, was from 12 to 16 cents a gallon. Benzole cost at the same time about $1 a gallon. Benzine is not acted upon by nitric acid, and hence cannot be employed in the manufacture of aniline colors. Chlorine, bromine, and iodine also produce no particular compounds with it. On comparison of benzole with benzine, it will thus be found that they differ widely from each other in boiling and freezing point, in molecular composition, in chemical reactions, in solvent properties, in specific gravity, and in their origin and uses. BENZOIC ACID (II, C,H 6 O 4 ), an acid which is abundant in the balsamiferous plants, and is produced artificially from bitter-almond oil, hippuric acid, and naphthaline. Gum benzoin, the product of the ityrax benzoin of the Asiatic archipelago, is the principal source of the sup- ply of benzoic acid. Common benzoin occurs in reddish lumps, which sometimes have a la- mellated fracture, and certain whitish opaque masses. When recent it emits an odor of bitter almonds. Gum benzoin appears to be composed of a mixture of three varieties of resin, with benzoic acid and a small quantity of a fragrant essential oil. Only one of the resins is soluble in ether ; a second is soluble in alcohol only. The white opaque masses appear to consist of the resin which is soluble in ether; they yield less benzoic acid than the brown portions. Benzoic acid may be extracted from powdered benzoin by boiling it for some hours with milk of lime, filtering the solution of benzoate of lime from the insoluble compound of resin and lime, and, after concentrating the filtrate, adding hy- drochloric acid. Benzoic acid is thus precipita- ted, and may be purified by sublimation. The acid is, however, generally extracted by the less economical but simpler process of direct subli- mation from gum benzoin, which contains 14 or 15 per cent, of the acid. If the resin be coarsely powdered and exposed to a tempera-