Azarin

(Dyeing.) A coal-tar coloring matter, bright red to crimson in tint, used as a dye for cotton fabrics. A'zo-, a word derived from azote (nitrogen) and used as a combining prefix in organic chemistry, or used separatively as an adjective form, as azo compounds. It is applied to compounds containing nitrogen, as nitric acid; and to those substitution derivatives of the aromatic hydrocarbons in which two atoms of nitrogen connect two similar hydrocarbon radicals of the benzene series, as azo-benzene. It is used to designate many of the coal-tar colors, as azo-blue, azo-diphenye, . Azo-colors, n. pl. ( Dyeing .) An important cla of artificial dye stuffs that have become prominent within recent years, belonging to a chemical group known as azo-compounds, of which the simplest in composition is azo-benzene. The formula of benzene is CH; that of azo-benzene, CHAN2CH. The group of derivatives is somewhat numerous. Both acid and basic azo-colors dye wool and silk readily, but need a mordant to dye cotton; but secondary azo-colors show strong affinity for cotton and can be used without the mordant. Benzo-purpurin is the most extensively used of the azo-colors. Azotized Bodies. A name frequently given to substances which contain, among their constituents, azote or nitrogen, and which occur in animals or plants as part of their living ti ues, or are found among the substance during their decay. Among the most important of these bodies is albumin , which occurs in white of eggs and forms an e ential part of the juices of organized bodies. In addition to the general form of albumen, it is found in special varieties, of which may be named globuline or crystalline , which is present in the crystalline lens of the eye; and vitelline , of which the yelk of the egg is principally made up. Other azotized bodies are fibrine , an abundant constituent of the muscles of animals and the seeds of plants; caseine , found in milk, and which is the basis of cheese; legumine , a variety of caseine which is common in the seeds of leguminous plants, such as peas and beans; gelatine , an important constituent of the skin and bones of some other parts of animals; chondrine , a variety of gelatine which finds its seat in the permanent cartilages and the cornea of the eye; isingla , a second variety of gelatine, whose source is the swim bladder of many of the fishes; and glue and size , secondary forms of gelatine. Urea, uric acid , and hippuric acid , found in the urine of the higher animals, are azotized substances resulting from the first steps of ti ue degeneration. In addition may be named kreatine and kreatinine , which occur in in the juice of flesh; urinary calculi , occurring as stones in the bladder; and the very numerous and important cla of substances containing nitrogen which are known as alkaloids , and include strychnine, morphine, quinine, and many other derivatives of plants. Nitrogen is present as an element in many other chemical compounds arising from the transformation of organic substance or decay of organisms, but the above named are the most important of their cla .