BUREAU OF MARKETS AND CROP ESTIMATES. 523 



tion regarding the strength of staple is being developed. A study 

 was made of cotton fibers, both microscopically and i)hotomicro- 

 grajjhically, as to their individual strength, spirality, and diameters. 

 Microscopic studies are made of immature staple, gin cut, and re- 

 ginned cotton, with a view to standardization. Apparatus and lab- 

 orator}- equipment are expected to arrive from abroad at an early 

 date, when activities will go forward along this line of investigation. 



COTTON TESTING. 



The division leader was assisted in this work by AV. G. Blair. 



Investigations have been made (1) to determine the relative 

 spinning value of three different varieties of cotton grown at Bard, 

 Calif., by the Bureau of Plant Industry during the season of 1920; 

 (2) to determine the comparative spinning value of Pima and 

 Sakellaridis cotton grown in California; and (3) to determine the 

 comparative spinning value of cotton compressed to different den- 

 sities. Laboratory tests were made to determine the strength of 

 individual fibers and yarn in connection with the manufacturing 

 tests. The spinning tests were conducted during the summer of 

 1921 at the North Carolina State College of Agriculture and En- 

 gineering, Raleigh, N. C, and from the last part of August to the 

 present time at the Clemson Agricultural College, Clemson College, 

 S. C. The laboratory tests were made in the cotton-testing labora- 

 torv at Washington. 



The results of the spinning tests on the three varieties grown at 

 Bard. Calif., and on the Pima and Sakellaridis cotton have been 

 reported to the Bureau of Plant Industry for use in its cotton- 

 breeding work. The results of the spinning tests of cotton com- 

 pressed to different densities have been prepared for publication. 

 The results of these tests showed that : 



Compressing cotton to standard or high density in a dry or normal con- 

 dition is not injurious to its spinning value. 



Compressing cotton in a damp condition to high density either increases the 

 percentage of waste or reduces the breaking strength of the yarn, or may 



do both. , .^ ^ ^v. 



Compressing cotton into a round bale with a hard core reduces the strength 

 of the yarn about 7 per cent. If the round bale were to be run continuously 

 in cotton mills, special opening equipment would be desirable. 



COTTON-MARKETING DEMONSTRATIONS. 



The division leader was assisted in this work by 0. S. ;Meloy. 



In cooperation with the extension service of several States, the 

 Division of Cotton Marketing continued to give cotton growers 

 instruction in the grading of their cotton, factors of value in cot- 

 ton w^ere explained, and methods of marketing and improving the 

 grade and character of the cotton produced were fully explained and 



demonstrated. , i- ,-. 



During the past year 30 communities formed organizations tor the 

 marketing of their cotton, as follows: Six in North Carolina. 4 in 

 South Cai-olina. 5 in Mississippi, and 15 in Texas. Over 110,000 

 bales were classed in these communities. According to reports re- 

 ceived the immediate financial profits to the growers from this 

 work ranged from one-half cent to 6 rents a pound, depending upon 



