12 
BULLETIN 1488, U. S. DEPARTMENT OF AGRICULTURE 
obtained by mixing from 15 to 30 bales of cotton in the opening room. 
If the bales were taken one by one and were not mixed, the manufac- 
tured product would probably show streaks of high and low quality 
rather than an average uniformity. 
22s WARP YARN, BLEACHED AND DYED (SKEIN) 
A portion of the 22s gray yarn of each grade was bleached and a 
portion bleached and dyed in a commercial mill. The effects of these 
processes upon the strength and brightness of the yarn were studied. 
All grades were treated at the same time, that the same conditions 
6 5 *+ 
GRADE NUMBERS 
Fig. 5.— Skein strength of 22s gray and treated yarns spun from eastern cotton. (21.1 turns per 
inch in yarn.) The gray yarn is stronger than the treated yarn of the same grade. The extent 
to which the double bleaching has decreased the strength of the yarn from that of the single 
bleach is shown 
might prevail in all cases. One lot was given a single bleach, a second 
lot was given a double bleach, and a third lot was dyed on the single- 
bleach base. The results of the strength tests on these lots are shown 
graphically in Figures 5 and 6. 
Single bleach reduced the strength of the eastern yarns approxi- 
mately 11 per cent. The double bleach reduced the strength of the 
eastern yarns 23 per cent. The double-bleached yarn was 13 per 
cent weaker than the single-bleached, indicating that double bleaching 
has a marked detrimental effect on the strength of the yarn. The 
dyed blue j^rns were 6 per cent weaker than the gray yarns. The 
above percentages are based on averages of the nine grades (fig. 5). 
