24 
Indian Forest Records. 
[Vol. Ill 
occupies at least one hour at 177°. A similar system of managing tem¬ 
peratures is in use in the manufacture of soda and sulphate wood pulps. 
The final conclusions drawn from this series of experiments are as 
under :— 
TABLE VI. 
To resolve the non-cellulose constituents of crushed and starch-free bamboo 
requires treatment as follows. 
— 
NaOH. 
Initial. 
Subsequent. 
O 
a> 
*8 
j 
3 
pj 
P 
B. P. 
Bleached yield, j 
Unit cost. 
Per cent. | 
pc 
EH 
Temp. 
i 
CD 
XJ1 
Ph 
1 
CO 
M 
a 
Temp. 
Press. 
E 
EG 
(a) 
Per cent. 
(b) 
Per cent. 
B. Tulda . 
! 16 
9f 
170 
100 
i 
162 
80 
4 , 
48-7 
32 
15-6 
43‘5 
7-12 
B. arundinacea . ] 
17* 
10* 
177 
120 
i 
162 
80 
4 
46-5 
37 
16-2 
42-0 
7-91 
B. 'polymor'pha . 
16 
9* 
177 
120 
i 
162 
80 
4 ' 
500 
36 
18-0 
44-5 
7-41 
C. pergracile 
16* 
10 
177 
120 
i 
162 
80 
4 
48-7 
35 
17-0 
43-5 
7-45 
Melocanna b. 
IS 
lOf 
177 
120 
2 
162 
80 
4 
47 
42 
19-7 
42*5 
8-33 
(а) Per cent, on unbleached pulp. 
(б) Per cent, on raw material. 
The quantities of NaOH used are in fair agreement with the estimated 
requirements given in Table V. In no case do they exceed the latter by 
more than *5 per cent, which may be regarded as the additional margin 
of safety to be provided against the slight variations in quality, composi¬ 
tion and condition of raw material when dealt with in large quantities. 
B. Tulda being slightly less lignified than the others required a lower 
initial temperature. Melocanna being more lignified required an extra 
hour at the higher temperature. The unbleached yield is, relatively to 
the bleached, too high, indicating that the former includes some pre¬ 
cipitation of colouring matter which might profitably be removed rbv 
a larger excess of NaOH, with a subsequent reduction of B. P. The 
column cc Unit cost ” is explained in the following paragraph. 
30. During the resolution and saponification of the non-cellulose matter 
by NaOH, coloured compounds, or groups of com- 
pounds, are formed which degrade the colour of 
the pulp to brown, but a large excess of the reagent has the effect of either 
reducing some, or all, of these to a lighter shade of colour, or of holding 
[ 204 ] 
