18 
BULLETIN 404, U. S. DEPARTMENT OF AGRICULTURE. 
The finish of the sheet is very poor, due to the fact that the calender 
stack was composed of very light rolls which did not have a satisfac- 
tory surface, yet the stack is known to be able to produce better finishes 
if the proper stock is employed. 
Run No. 136 was made on the 300-pound portion of stock from 
cooks Nos. 293, 294, 295, and 296, and in essentially the same manner 
as run No. 135. The stock was washed one hour, but given a brush 
of three hours, and this brush was harder than in run No. 135. 
Bleach to the extent of 19.8 per cent of the fiber was used, assisted 
by 1 pint of oil of vitriol, and the resulting color was an improvement 
over that of run No. 135. After adding 13.5 per cent of clay and 
sizing with 1.1 per cent of resin size, the furnish was given one-half 
hour's light brush, tinted, and run on the machine, which was set 
at 70 feet per minute. This stock acted better on the wire and gave 
no trouble on the machine, but it still seemed to be impossible to 
reduce the wood shives by manipulation of the Jordan refiner. The 
resulting sheet is an improvement over that produced by No. 135, 
but is far from satisfactory. 
Run No. 138 was made from hurds which, as in all subsequent tests, 
were sieved on a ll§-mesh wire screen until practically all the loose 
dirt and sand was removed, which operation caused a loss averaging 
3 per cent of the hurds. Stock from cooks Nos. 302 and 303 was 
used for this run and the increased amount of caustic soda and the 
increase in the time of cooking gave a stock of better appearance than 
those of preceding tests. 
The stock, amounting to 231 pounds dry weight, was washed and 
at the same time given a light brush for one hour only, after which 
it was bleached with 17 per cent of bleach without the addition of 
acid. Since the preceding paper appeared somewhat weak and had 
a low tearing quality, it was decided to use a furnish of 15.7 per cent 
bleached sulphite and 84.3 per cent bleached hemp-hurd stock. 
After loading with 13.1 per cent of clay and sizing with 1.1 per cent 
of resin size, the furnish was given a medium brush for one hour, 
tinted, and run on to the machine at 70 feet per minute. The stock 
gave no trouble on the machine, but it was impossible to judge the 
effect of the Jordan refiner, because through an oversight the machine 
chest had not been cleaned since previous use on an unbleached 
yucca material. It is believed, however, that sheet No. 138 shows 
improvement in the preparation of the hurd pulp. 
Run No. 139 was made from stock of cooks Nos. 304 and 305, 
in which still more caustic soda was employed and the time and tem- 
perature of cooking were increased, giving a yield of total fiber of 
40.7 per cent of the sieved or 39.4 per cent of the unsieved hurds, 
The cooked stock still seemed to be undertreated, but it must be 
remembered that in working with any new raw material it is impos- 
