COWPEA 



DYES AND DYEING 



267 



Reports 1892, 1893, 1895 ; Georgia Experiment 

 Station Bulletins, Nos. 3, 17, 23, 26 and 71; 

 Illinois Experiment Station Bulletin, No. 94 ; Ken- 

 tucky Experiment Station Bulletin, No. 98; Report, 

 1902 ; Louisiana Experiment Station Bulletins, 

 Nos. 8, 19, 29, 40, 55 and 72; Michigan 

 Experiment Station Bulletins, Nos. 224 and 227; 

 Mississippi Experiment Station Bulletin, No. 40; 

 Missouri Experiment Station Bulletin, No. 34; 

 New Jersey Experiment Station Bulletins, Nos. 

 161, 174 and 180; Report, 1893; North Carolina 

 Experiment Station Bulletins, Nos. 73, 98 and 162; 

 Oklahoma Experiment Station Bulletin, No. 68; 

 Reports 1899, 1901 and 1905; South Carolina 

 Experiment Station Report, 1889; Texas Experi- 

 ment Station Bulletin, No. 34; Vermont Experi- 

 ment Station Report, 1895; Pennsylvania Experi- 

 ment Station Report, 1895; Bulletin, No. 130; 

 United States Department of Agriculture, Bureau 

 of Plant Industry Bulletin, No. 25; United States 

 Department of Agriculture (Agrostology 64), Cir- 

 cular, No. 24; United States Department of Agri- 

 culture Yearbook for 1896. 



DYES AND DYEING. Pigs. 372-378. 

 By C. S. Doggett. 



Dyestuff materials are derived from the animal 

 and vegetable kingdoms, and, in the last fifty years, 

 those made synthetically from products obtained 

 from coal-tar. In 1856, W. H. Perkin, an English 

 chemist, discovered the production of a violet dye 

 when experimenting with aniline, a body found in 

 coal-tar ; soon afterwards, other dyes were made 

 from the same products and they became known as 

 aniline colors. Unfortunately, these colors were 

 inferior to the natural coloring matters, which 

 they surpassed in brilliancy, so that, although very 

 many artificial colors have been made that equal or 

 surpass those derived from natural products (in 

 some instances the identical natural product being 

 made synthetically), "aniline colors" even today 

 are regarded in the popular mind with more or less 

 suspicion. Over twenty-five thousand patents have 

 been taken out covering these dyes or processes 

 relating thereto, and more than two thousand arti- 

 ficial dyestufiis have found more or less commercial 

 value. The natural coloring matters are rapidly 

 becoming of historic interest only and their cul- 

 ture is being abandoned. A few are now secured 

 from native trees of the forest. Twenty-five years 

 ago madder began to be replaced by alizarine, 

 the coloring principle found in it, which is now 

 manufactured in enormous quantities ; and within 

 the last six years, the artificial production of indigo 

 has been compelling the producers of the natural 

 product to improve their methods or succumb. 

 Indeed, it is only the cheap labor of India that 

 renders any competition possible. 



Dyestuffs are used for coloring all sorts of 

 materials. Addition of coloring matter to a food 

 product to disguise its appearance or character 

 partakes of the nature of fraud. Harmless color- 

 ing materials may be used in confectionery and the 

 like, where it is evident that no deceit is intended. 



Coloring materials vary so much in properties 

 that it is not possible in this place to give the de- 

 tails of their extraction. Coloring matters that 

 exist as such are extracted with the proper solvent : 

 water-alcohol and ether are the chief solvents. 

 Many, of the natural coloring matters, such as that 

 of logwood, are not found in plants in the free 

 state, but in combination with a glucose-like body, 

 and are called glucosids, and only after a kind of 

 fermentation or oxidation is the coloring principle 

 in condition to be extracted. In common with many 

 plants possessing medicinal properties, the special 

 ferment also exists in the plant, so that fermen- 

 tation proceeds when the proper conditions are 

 met. 



List of natural animal and vegetable colors. 



The following very complete list of natural col- 

 ors of vegetable and animal origin, compiled by 

 Wilton G. Berry and published in Circular No. 

 25, of the Bureau of Chemistry, Department of 

 Agriculture, rescues from oblivion many coloring 

 matters and fairly indicates their importance and 

 use. The source of the color is given in Italics : 



Alder bark : Alnus glutinosa. Yellow. 



Alkanet : Baphorhiza tinctoria (Alkanna tinctoria, 

 Anehusa tinctoria). Used in coloring oils, medicines, po- 

 mades, wine, etc. Red to crimson. Alkanna green has 

 also been prepared from the root. 



Aloes : Cape aloe (Aloe spicata), A. arborescens, A. 

 lucida, A, Succotrina, A. vera. Yellow. 



Al root or Aich root, soorangee, suranjee (India) : 

 Morinda eitrifolia, M. tinctoria. Alumina lake, yellow. 



Annatto, or anotto, orlean, roucou, orenetto, attalo, 

 terra orellana, achiote : Bixa Or'ellana. Used for color- 

 ing oils, butter, etc. (Fig. 372'.) 



Archil, or orchil, orseille, oricello, orohilla : Rocella 

 Hfontagnei (new), B.fuciformis (old), B. tinctoria. Also 

 prepared from any lichens containing orcin or its deriv- 

 atives, i. e., Variolaria, Lecanora, Evernia, Cladonia, 

 Ramalina, Usnea. Appears in liquid, paste, and powder 

 forms, the latter being a sulfonated derivative. Dyes 

 unmordanted wool in neutral, alkaline and acid solutions, 

 giving a bright bluish red. The color is not fast to light. 



Asbarg or gandhaki (Afghanistan) : Delphinium Zalil. 

 Yellow lakes prepared from the blossoms. 



Bahia wood : Ccesalpinia Brasiliensis. Exported from 

 Bahia. Sometimes called Brazilwood. See under Red- 

 woods. 



Barberry : Berheris vulgaris. Yellow basic dye. 



Barwood, or camwood, kambe wood, bois du cam : 

 Baphia nitida. From west coast of Africa and Jamaica. 

 See under Redwoods. 



Bastard hemp : Datisea cannabina. Alkaline solutions, 

 yellow. 



Bilberry, or whortleberry : Vaccinium membranaceum, 

 V. Myrtillus. Blue to purple. 



Box myrtle, or yangmoe of China, kaiphal of India : 

 Myrica Nagi (M. sapida and M. integrifolia), M. rubra. 

 Alumina lake, brown orange. 



Brazilwood, or fernambourgwood, pemambuco wood, 

 fernambuck wood, bois de fernambuoc, rothholz : Guilan- 

 dina crista, Ccesalpinia Braziliensis. Chiefly from Brazil 

 and Jamaica. See under Redwoods. 



Brazilettowood, or Jamaica redwood, Bahama redwood : 

 Balsamea sp. See under Redwoods. 



Buckthorn: Rhamnus cathartica. Purple juice which 

 when treated with alkali becomes green. Used in confec- 

 tionery as sap green. 



