COMPARATIVE SPINNING TESTS. 3 



exactly the same conditions for each kind of cotton used, so that the 

 waste percentages might be comparable. 



The different lots of cotton were run on the same fly or roving 

 frames and spinning frames throughout for the different numbers of 

 yarn; that is, all cotton going into any certain number of yarn was 

 subjected to the treatment of the same machines, and, where possible, 

 the different lots were placed and rmi simultaneously through each 

 process. Table I gives the respective drafts used in these machines. 



- " Table I. — Drafts used in the manufacture of each number (f yarn. 



Num- 

 bers. 



Slubber. 



First 

 interme- 

 diate. 



Second 

 interme- 

 diate. 



Jack 

 frame. 



Spinning 

 frame. 



lO's... 

 20's . . . 



30's... 

 40's . . . 

 50's... 

 60's... 

 80s... 

 lOO's . . . 



3 



3 



3 



3 



3 



3 



3.63 



4 



4 



4.5 



4 



4 



4.17 



4.5 



5 



5.30 



5 



6 



5 



5 



5.5 



6 



6 



6.25 





8 

 11.9 



8.26 

 10 

 10 

 10 

 10 

 10 





6 



6.42 



7 



7.12 



7 



7.25 



While the cotton was being manufactured, the humidity condi- 

 tions were kept as nearly constant as possible. Records were taken 

 hourly and the humidifiers were regulated accordingly. Records 

 were taken also every thirty minutes during the time the tensile 

 strength tests were being conducted. The desired point of relative 

 humidity was 55 per cent in the raw cotton and picker rooms, 55 to 60 

 per cent in the card room, 60 to 65 per cent in the spinning room, 

 and 65 per cent in the yarn-testing room. Moisture tests were made 

 also on samples of cotton selected from each place in the processes 

 where the stock was weighed, and it was found that the differences 

 in the percentages of moisture were comparatively small. 



The spinnmg qualities of the different lots of cotton were judged in 

 the following manner: 



A broken end on a spinning frame was not pieced up until deter- 

 minations were made as to the causes of the breakage. All ends 

 breaking down, unless due to some mechanical defect, were charged 

 against the particular grades or lots in which they occurred, and nota- 

 tions were made as to the amount of fly waste from the different lots. 



There was no conclusive evidence of superiority in any one lot over 

 any other in spinning. In a number of cases, the bobbins of each lot 

 filled up on the spinning frames without an end breaking down. 



GRADE, STAPLE, AND PRICE COMPARISONS. 



In order to understand better the comparative relations between 

 the lots of cotton to be used, samples were presented to a committee of 

 cotton specialists of the Office of Markets and Rural Organization. It 

 was thought that, judging from the general appearance of the different 



