8 
Indian Forest Records. 
[Vol. Ill 
10. Air-dry bamboo differs considerably from other materials in its 
capacity for bolding and retaining hygroscopic 
Moisture. \ , J rm- • j & . 4.1 i • , . / 
moisture. This is due to the large interior surface 
which the pores expose to the effect of changes in the humidity of 
the atmosphere-changes which, in a climate like that of India, with its 
distinct wet and dry seasons, are naturally greater than in temperate 
latitudes where the hygrometric state of the air is more constant through¬ 
out the year. I have tested samples after a prolonged period of dry 
weather to contain 4*75 per cent, of moisture only. The same sample, 
kept until the monsoon season was well advanced, carried 12 per cent, 
and I have found as much as 15 per cent, in exceptional cases without it 
being noticeably damp either in appearance or to the touch. It is also 
quickly sensitive to merely temporary and slight changes in atmospheric 
conditions; thus, the sample mentioned above as having 4 75 per cent, 
of moisture after a lengthy period of dry weather, contained 9 per cent, 
a few days later, one day of showery weather having intervened. It is 
therefore highly necessary, when making tests of yield, to ascertain the 
moisture and either deal with the results on an absolutely dry basis or on 
a recognised standard of normal air-dryness, otherwise contradictory 
results from this cause alone may easily ensue. Such a precaution is 
always taken in laboratory work but is sometimes overlooked in factory 
tests, and it is quite possible some of the variations reported may be, 
in part, due to such neglect. A 10 per cent, variation in the moisture 
contents of the raw material may easily be responsible for 4 to 5 per cent, 
difference in the reported pulp yield. The English normal air dry stand¬ 
ard of 90 per cent, dry substance and 10 per cent, of moisture appears to 
be a fair mean throughout the year and I have therefore adopted it for 
both raw material and product. 
11. In their treatment of bamboo, it has been natural for experiment- 
.. alists to rely largely upon their experience with 
Mechanical treatment. .„ £ 
coniferous wood to which it has many points 01 
resemblance in appearance, structure and chemical constitution. Its 
preliminary preparation for digestion has therefore consisted of cutting 
out and rejecting the nodes, which have been found intractable at the 
pressures hitherto available, and reducing the internodal portions to chips. 
But there does not appear to have been sufficient attention given to those 
features in which it is markedly dissimilar to wood. In chemical con¬ 
stitution it presents no difficulty. As with all chemical reactions, if the 
requisite quantity of reagent is present under suitable conditions, it is 
bound to do its work, provided it can get at it. But in its combined mass, 
colloidal and capillary air resistance to the penetration of solvents, 
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