14 
BULLETIN 1488, U. S. DEPARTMENT OF AGRICULTURE 
There is a marked similarity between the results of the single- 
strand tests and of the skein tests, although the results do not check 
in every instance. It is possible that such differences may be due 
to the fact that single-strand tests do not cover so large a quantity 
of yarn as do the skein tests. 
6 5 t* 
GRADE NUMBERS 
Fig. 7.— Strength in ounces per single strand of 22s gray and treated warp yarns spun from the 
eastern upland cotton. (21.1 turns per inch in yarn.) The gray yarn is stronger than the 
treated yarns. The double bleach has decreased the strength of the yarn from that of the single 
bleach 
28s TWO-PLY YARN (SINGLE STRAND) 
The 28s two-ply yarn, mercerizing twist, spun from each grade of 
cotton was bleached; bleached and mercerized; and bleached, mer- 
cerized, and dyed. These yarns were broken by the single-strand 
method, the results of which were corrected on the basis of the size 
of gray yarn. The average strength of yarns finished by two plants 
is shown graphically in Figures 9 and 10. 
The results of single-strand tests of the two-ply yarn show a 
tendency for the yarns spun from the higher grades to have a greater 
breaking strength than those spun from the lower grades. 
