SPINNING TESTS OF COTTON. 6 
Ginners' compress hale. — A ginners' compress bale (PL III) is made 
in exactly the same manner as the flat bale only greater pressure is 
applied. The gin box and apparatus are made more rugged to with- 
stand the greater pressure when compressing the loose cotton to this 
higher density. This type of bale usually has six ties. Its density 
varies from 25 to 30 pounds per cubic foot, depending upon the 
amount of cotton in the gin box. 
This type of bale was not included in this study because of the 
small number of gin compresses in use and inability to secure a 
pure strain of cotton from such a compress. 
CONDITIONS OF THE TESTS. 
The general conditions of the tests follow, and specific information 
regarding details of results are found under the descriptions of the 
separate tests. 
VARIETIES OF COTTON TESTED. 
The varieties of cotton tested consisted of pure strains of Cleveland 
Big Boll, Rowden, Delta, and Webber 49 grown by men of reputa- 
tion for their plant-breeding work. 
The Cleveland Big Boll, Delta, and Webber 49 cottons were 
grown during the season of 1920 under normal weather conditions up 
to the time of picking. At this time, the rainfall delayed the opening 
of the bolls so that the number of pickings was reduced. 
The climatic conditions during the season of 1921, under which 
the Rowden cotton was grown, were normal for the first half of the 
season followed by an extended drought which seemed to have the 
effect of shortening the length of staple. 
All of the bales of the same variety of cotton were picked at the 
same time, ginned on the same day on the same battery of gins, 
and compressed on the same day with the exception of the round 
bale of the Rowden variety which was ginned on a different gin than 
the rectangular bales. 
The reason for securing pure strains and proceeding as described, 
was to eliminate as many variables as possible with each variety, 
thus placing the variable of compression to different densities upon 
a strictly comparative basis. The test on each variety is therefore 
a separate test. 
Detailed information regarding the cotton selected for the tests is 
shown below. 2 
Variety. 
Grown at— 
Sea- 
son. 
Grade. 
Staple. 
Stored 
in bale. 
Cleveland Big Boll 
Hartsville, S. C 
Wills Point, Tex 
1920... 
1921... 
1920... 
1920... 
Inches. 
H 
l 
li 
n 
Months. 
6 
Rowden 
Strict Middling 
6 
Delta 
12 
Webber 49 
Hartsville, S. C 
9 
2 The cotton was classed by members of the board of examiners, a committee authorized to class cotton 
at the future exchanges under the provisions of the United States cotton futures act. 
