UTILIZATION OF AMERICAN FLAX STRAW. 
11 
suits of one series of tests on a lime-cooked flax-straw paper are 
here given (Table V). The Avet sheets were placed on a cloth- 
covered iron cylinder heated by steam to 103° C. and held down by 
placing on top a cloth which was maintained at a definite tension. 
The sheets shrank more and cockled more under a light tension than 
under an increased tension. The physical tests were made at 80° C* 
and 65 per cent relative humidity (fig. 3). 
Table V. — Effect on the physical constants of paper dried under different 
tensions. 
550 grams . . 
1,245 grams. 
2,155 grams. 
3,240 grams. 
3,700 grams. 
0. 00312 
. 00407 
. 00487 
. 00571 
. 00405 
From Table V it appears that within certain limits the strength 
and folding quality of a sheet depend to a considerable degree upon 
the method of drying. - 
Bleaches were made with from 12 to 25 per cent of burned lime, 
calculated on the bone-dry weight of the straw used, employing 
temperatures from 135° to 170° C. and treating at the definite tem- 
perature from 6 to 10 hours. 
The most thorough reduction and generally satisfactory results 
were obtained with 11 per cent of lime acting for 10 hours at 170° C, 
or the equivalent of 100 pounds steam pressure. The yield of total 
fiber obtained did not vary much with the different bleaching condi- 
tions, ranging from GO to 68 per cent of the bone-dry weight of the 
original straw employed. Determinations of the yield of washed 
or separated fiber on the satisfactory bleaches gave an average of 32 
per cent of the bone-dry weight of straw employed. 
MILL TESTS ON THE MANUFACTURE OF WRAPPING PAPER. 
Tests of wrapping paper from flax straw were made at Cumber- 
land Mills, Me. Semicommercial machines were used, and most of 
the work was performed by the regular mill employees. 
The straw used in these tests was raised in the vicinity of Fargo, 
N. Dak., being the same as that used in the laboratory tests. It was 
first sieved on a 4J-mesh screen, in order to remove the loose chaff 
composed of dirt, seeds, and empty seed capsules, which amounted 
in total to 24.5 per cent of the original straw. 
