16 
BULLETIN 404_, TJ. S. DEPARTMENT OF AGRICULTURE. 
located in the bottom of a circulating trough and the other set on the 
periphery of a roll revolving just above the former set of knives. It 
is during this operation that the loading and sizing agents are incor- 
porated and the whole furnish is tinted either to produce a satisfac- 
tory white or the desired color. 
The term " paper making," as used in this publication, means the 
operation of forming the finished sheet of paper from stock which has 
been furnished and prepared in the beater. In these tests a 30-inch 
Fourdrinier machine of regular construction was used, a machine 
which often is used for the production of paper for filling regular com- 
mercial orders. The machine is designed to cause the water suspen- 
sion of fibers to flow on to a traveling wire cloth, whereby the water 
drains away. More water is removed by passing the wet sheet through 
a series of press rolls, after which the sheet is dried on steam-heated 
drums and passed through polished iron rolls, which impart a finish 
to the sheet. A Jordan refining machine was employed in conjunction 
with the machine to improve further the quality of the fiber, and a 
pulp screen was used in order to remove coarse and extraneous mate- 
rials from the fiber. 
DESCRIPTION OF TESTS. 
The nature of each complete paper test and the dependence of 
each operation on the others were such that it does not seem advisable 
to submit the results of the seven tests in tabular form. The numer- 
ous cooks, however, which furnished the pulp for the paper tests are 
presented in Table I in all essential detail. 
Table I. — Data on cooking hemp hurds. 
Caustic 
soda used 
(percentage 
of bone-dry 
hurds). 
Strength of 
caustic soda 
(grams per 
liter). 
Causticity 
of soda 
solution. 
Cooking. 
Yield of 
bone-dry 
Cook No. 
Time 
(hours). 
Tempera- 
ture (°C.) 
fiber (per- 
centage of 
bone-dry 
unsieved 
hurds). 
293 
20.6 
21 
21.6 
20.3 
21.9 
24.4 
24.2 
25 
25 
27.8 
26.7 
26 
27.3 
27.1 
27.2 
28.3 
29.1 
29.1 
29.4 
30 
29.6 
29.6 
29.4 
29.3 
100 
100 
100 
100 
100 
100 
100 
100 
100 
107.5 
107 
107 
107 
107 
107 
116.5 
113.1 
109 
109 
109.5 
109.5 
107 
107.5 
107.5 
75.3 
75.3 
75.3 
75.3 
82.5 
82.5 
84.3 
84.3 
84.3 
84.3 
84.4 
84.4 
84.4 
84.4 
84.4 
85.5 
84.9 
83.9 
83.9 
84.9 
84.9 
84.8 
84.2 
84.2 
3 
3 
3 
3 
4 
4 
4 
4 
5 
4 
5 
5 
5 
6 
6 
5 
5 
5 
5 
5 
5 
5 
5 
5 
166 
166 
166 
166 
166 
166 
166 
170 
170 
166 
170 
170 
170 
170 
170 
170 
170 
294 
295 
296 
301 
0) 
302 
303 
44.1 
304 
39.5 
305 
39.4 
306 
36.5 
307 
38.1 
308 
} 37.3 
309 
310 
37.0 
311 
36. S 
312 
35.9 
313 
1 ' 
314 
170 / 
315 
170 
170 
170 
170 
170 
170 
34.9 
316 
37.2 
317 
37.0 
318 
37.7 
319 
} 35.4 
320 
1 Stock not used; dirty. 
