SPINNING TESTS OF UPLAND LONG-STAPLE COTTONS. 7 



CARD WASTE. 



The function of the pickers is to remove from the cotton all the 

 heavier impurities such as sancl, hulls, stems, bunches of neppy fibers, 

 broken seed, etc., while the card removes the smaller impurities such 

 as neps, tangled fibers, minute particles of trash and leaf, and a small 

 percentage of short fibers. The card waste is itemized in Table III. 



Table III. — Percentage of each type of card waste obtained from each variety. 





Variety. 





Durango, 

 grade 

 G. x\L 



Columbia, 



grade 

 S. G. M. 



Lewis, 

 grade 

 G. M. 



Webber 



No. 1, 



grade M. 



Webber 



No. 2, 



grade M. 



Delta 

 blended. 





0.69 



2.41 



.86 



0.85 

 2.53 

 . 75 



0.73 

 2.40 



.57 



1.12 

 2.62 



1.46 



1.82 

 2.54 

 1.45 



1.62 





3.64 



Licker in and screen waste s . . . 



1.77 



Total card waste 



3.96 



4.13 



3.70 



5.20 



5.81 



7.03 



1 Card stripping waste is composed of short fibers that slip down in the spaces between the wire^ of the 

 card clothing. This waste is chiefly composed of fibers up to about f to h inch in length with some longer 

 fibers. 



2 Flat stripping waste is composed of neps, tangled fibers, gin-cut or damaged fibers, motes, and all those 

 fibers that do not readily disentangle and which adhere to the fiats. 



3 Licker in and screen waste is composed of extremely short fibers and minute particles of seed, sand, leaf, 

 stalks, etc., and those fibers that fly from the general mass and drop -through the screens underneath the 

 card. 



RELATION OF GRADE TO WASTE. 



When the cotton has passed the card almost all foreign matter has 

 been removed. The greater part of those fibers below three-eighths 

 to one-half inch in length have also been separated. A glance at 

 Table I will show that the Webber bales contained from 4 to 5 per' 

 cent more foreign matter than the other three, but it must be noted 

 that the grade of these two is middling, while the others are good 

 middling and strict good middling. The mixture of Delta cotton, 

 which averaged slightly better than middling, compares closely with 

 Webber. Thus 4 to 5 per cent on a 500-pound bale amounts to 20 to 

 25 pounds of cotton waste. This at 20 cents per pound amounts to 

 $4 to $5 per bale, a difference equal to 80 to 100 points in value. 



It is now of interest to compare the waste percentages up to and 

 including the card in the case of the two middling bales with that 

 of the two good middling bales. The total waste itemized in Tables 

 I, II, and III is obtained by adding the picker waste, card waste, and 

 invisible loss. The tAvo middling bales show an average of 15.11 

 per cent, and the good middling an average of 9.34 per cent, a differ- 

 ence of 5.77 per cent in favor of the good middling. However, it must 

 be stated that this does not represent the true relation of values 

 between grades, as there are a number of other factors which in- 



