The real objection to these widely distributed popular dyes is a very different one. They are not sold under their own names, and therefore it is almost impossible to identify them. To be sure, from the accompanying directions it is possible for a trained dyer to recognize at once the class to which the dyestuff belongs. But it is impossible for him, excepting after a long, tedious and often very troublesome analysis, to tell just what member or members of that particular class is contained in any given package. For this reason the dyer who has to depend on them for an important piece of work is in much the same position as a doctor would be who had to treat a difficult case with patent medicines compounded after secret formulæ. In the following chapters, a discussion of each class of dyestuffs, and an explanation of their application and general properties will be followed by lists of three or four of the very best colors, sold by the New York agents of six of the largest and most reliable color manufacturers. Workers wishing to obtain these dyes in comparatively large quantities, say one pound and upwards, can get them by writing directly to the addresses in the following table: _Badische_— The Badische Anilin & Soda Fabrik, 128 Duane St., N. Y. City. _Cassella_— The Cassella Co., 184 Front St., N. Y. City. _Elberfeld_—The Farbenfabriken of Elberfeld Co., 117 Hudson St., N. Y. City. _Kalle_— Kalle & Co., 530 Canal St., N. Y. City. _Klipstein_—A. Klipstein & Co., Agent for Society of Chemical Industry of Basle, 654 Greenwich St., N. Y. City. _Metz_— Farbwerke-Hoechst Co., formerly H. A. Metz & Co., Agent for the Meister Lucius & Bruning Co., 122 Hudson St., N. Y. City. N. B. Further information concerning dyestuffs, apparatus, textiles, chemicals, etc., connected with this work may be obtained on writing to the author at 7 West 43rd St., New York. THE NAMING OF MODERN DYESTUFFS It is important to remember that, in order to identify a color by name, it is necessary to know three things: first, the trade name; second, the shade, or distinguishing, letter; and third, the manufacturer or agent. The trade name sometimes bears a reference to the class, properties, or color of the dye, as “fast acid blue”; or to its chemical composition, as “methylene blue,” or “diamine red”; but in most cases it is simply an arbitrary name, given by the original discoverer when the patents were issued, or assigned later by the manufacturer or his local agents.