BULLETIN OF THE 



No. 62 



Contribution from the Bureau of Plant Industry, Wm. A. Taylor, Chiel 

 January 14, 1914. 



TESTS OF THE WASTE, TENSILE STRENGTH, AND BLEACHING 

 QUALITIES OF THE DIFFERENT GRADES OF COTTON AS 

 STANDARDIZED BY THE UNITED STATES GOVERNMENT. 



By N. A. Cobb, Agricultural Technologist in Charge of Agricultural Technology and 



Cotton Standardization. 



ORIGIN AND LOCATION OF THE EXPERIMENTS. 



The Department of Agriculture is not interested directly in textile 

 work. Its interest is indirect and arises largely from the fact that 

 Congress has selected it as the governmental agent for the establish- 

 ment of the official cotton grades and for the study of cotton standard- 

 ization. Many of the experiments of the department are therefore 

 directed toward ascertaining certain facts that will assist in making 

 the official cotton grades more useful and more reliable. 



The official cotton grades at present take cognizance of only two 

 of the important qualities which determine the value of cotton, 

 namely, (1) the color and (2) the amount of trash and waste matter. 

 Any complete system of standardization of cotton will, however, 

 have to take into consideration, among other things, (3) the length of 

 the fiber, (4) the strength of the fiber, (5) the clinging qualities of the 

 fiber, and (6) the bleaching qualities of the fiber. Most of these 

 qualities are of such a nature that they can be satisfactorily deter- 

 mined only by means of spinning tests, and it is for this reason that 

 the department for several years has been making spinning tests 

 with cotton in the mills and textile schools of the country. Experi- 

 ments have been undertaken, among other places, at the following 

 institutions and miUs : Clemson Agricultural College, Textile Depart- 

 ment, Clemson, S. C, Lowell Textile School, Lowell, Mass., Mississippi 

 Agricultural and Mechanical College, Agricultural College, Miss., 

 North Carolina Agricultural and Mechanical Textile School, Raleigh, 

 N. C, and at various mills in South Carolina, North Carolina, Missouri, 

 Virginia, Massachusetts, and Maine — about a dozen different mills in 

 all. The experiments consisted in spinning cotton of known history 

 into yarn under definite conditions as nearly as possible approaching 

 commercial conditions. The qualities of the resulting yarn have 

 been tested, and by comparison the desired results have been secured. 



