Part III.] Raitt : Bamboo as Material for Paper-pulp. 9 
bamboo presents difficulties of treatment as to its internodal 
portions greater than those of wood, and so much greater in the 
case of the nodes, that no serious attempt has been made to deal 
with them. In short, the special difficulties met with in bamboo 
are physical and not chemical and must be, and can be, dealt with 
by physical and mechanical means. If bamboo is crushed instead of 
chipped, its special difficulties disappear, not only with internodes but 
also in the case of nodes. The crushing requires to be very thoroughly 
done, my best results having been obtained at the Allahabad Exhibition 
(in December 1910), by passing the culms split in half (i.e., split once 
longitudinally), through the heavy cane crushing rollers of a modern 
sugar plant. With small thin walled bamboo, splitting is not necessary. 
This treatment results in the production of loose masses of finely divided 
fibrous bundles somewhat like hanks of coarse tow. The crushing frac¬ 
ture runs along the capillary tubes splitting them open, expelling the air 
and exposing their inner surfaces to immediate attack by the chemical 
solvents. The nodes almost disappear, it being difficult to tell what por¬ 
tion of the fibrous mass was node and what internode. The air resistance 
is totally destroyed thus saving the time occupied by its expulsion in the 
digestion of chips, and reference to Table II will show that its expulsion is 
so complete that the sp. gr. is actually slightly raised. When thrown 
into water, crushed bamboo of the heavier species sinks at once, while the 
lightest float for ten minutes only; thus we get rid of the floatation 
trouble with its resultant irregularity of digestion referred to in paragraph 
5. The colloidal resistance also largely disappears. This will be under¬ 
stood by the somewhat rough analogy of the behaviour of resin in the 
process of making resin soap. If a lump of resin is thrown into a boiling 
solution of NaOH, there immediately forms on it a thin colloidal film of 
partially dissolved resin which exercises a water-proofing protective 
effect on the interior of the lump and considerably delays its saponifica¬ 
tion. But if the resin is first crushed to powder and added in that con¬ 
dition slowly to the boiling liquor and prevented by stirring from again 
cohering into a mass, complete and rapid saponification results, the 
immensely greater surface area, provided by the small particles to 
the action of the liquor, preventing the establishment of colloidal pro¬ 
tection. Similarly in crushed as compared with chipped bamboo, the 
much larger surface area presented, and the reduction of pectous films 
and ligneous masses from thick to thin and large to small, very consider¬ 
ably reduces the colloidal resistance. By crushing, the node difficulty 
is entirely removed and the bamboo can be dealt with as a whole, the 
nodes being reduced to a physical and mechanical condition indistinguish- 
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