TESTS OF OFFICIAL COTTON STANDARDS FOR GRADE. 19 
after which they were hydro-extracted and treated in a circulat- 
ing vat. 
Bleaching.—The goods were placed in the center of a 300-pound 
load of commercial yarns, the ratio of liquor to the goods being in 
weight 10 to 1, and treated for 14 hours with a 2.5-degree Twaddell 
solution of bleaching powder containing 1.26? grams of chlorine per 
liter. The goods were-treated with a 1-degree Twaddell solution of 
sulphuric acid containing 6.80 * grams per liter and then washed for 
30 minutes. Finally, the goods were soaped 30 minutes in a solution 
containing 2 per cent* of 88 per cent soap chips. The skeins were 
blued by treating them 20 minutes in a water solution containing 
0.055 per cent of methylene blue. After the skeims were hydro- 
extracted they were dried for 34 hours on a truck drier heated to a 
temperature of 120° F. | 
Qualities of bleach.—The grades in the order of whiteness obtained 
by bleaching are as follows, beginning with the best: 
Good Middling, western. Middling, eastern. 
Good Middling, eastern. Low Middling, western. 
Middling Fair, western. Low Middling, eastern. 
Middling Fair, eastern. Good Ordinary, western. 
Middling, western. Good Ordinary, eastern. 
Cotton yarn made from Low Middling western upland and Low 
Middling eastern upland cotton produced goods haying a somewh&t 
slaty hue. Yarns made from the Good Ordinary, both eastern 
upland and western upland cotton, did not bleach satisfactorily in 
that a decided bluish cast was apparent. 
TEXTILE-SCHOOL TESTS. 
Subsequent tests were made in the New Bedford Textile School 
in order to check the determinations made in the commercial bleach- 
ery. They included tests of the whiteness, tensile strength, weight 
losses, and moisture content at each operation. 
Scouring.—The scouring * was done with 10 per cent soda ash 
and 5 per cent soap. The goods were boiled five hours, rinsed well 
with hot water at 75° C. and then in cold water at 23° C., after 
which they were acidulated with 1 per cent solution of sulphuric 
acid, rinsed freely in water until free from acid, and dried. 
Bleaching.—Samples of the wet yarn were taken after the last 
rinsing and bleached at 23.3° C. in a solution of bleaching powder 
containing 2 grams per liter of chlorine. The goods were left in this 
1 This vat was constructed in such a way that the skeins were supported by rods in a comparatively 
loose condition, and the liquor was circulated through them by mechanical means. 
2 The liquor was kept overnight in a well-corked bottle and the analysis was made on the following 
morning. 
3 The percentages given in the bleaching tests are calculated on the weight of goods treated unless other 
wise stated. 
4 The volume of liquor used in the textile-school tests was fifteen times the weight of the goods treated. 
