f 
34 REPORT ON THE CAOUTCHOUC OP COMMERCE. 
the gr^jlhd and establish itself, and would be consequently all this 
time would be saved. 
Mr. Mann calculates that even commencing at 50 years, the 
clear profit of a tree, tapped every third year, and lasting to 
100 years old, would be 320 rupees of Caoutchouc, beside 250 rupees 
of lac. Each third year a tree, of 50 years old, would yield 40 lbs. 
of very pure Caoutchouc, but a planted tree could be safely tapped 
at 25 years, though its yield would not be so great as an older tree. 
Preventative measures should be adopted both in the case of 
present trees and any which may be planted, by limiting the time 
of tapping, guarding against over-tapping, and not allowing binding 
or total destruction of * a tree. It would be well to divide the 
various forests into districts so as only to allow tapping during the 
months of January, Eebruary, and March, in every third year in 
each district. The question of leases is an important consideration, 
and I believe that it will be found necessary either to extend the 
leases to a much longer period, in order to render it advantageous 
to the interest of the holder, to take the greatest possible care of 
the trees or for the Government to take it entirely into their own 
hands and not grant leases at all. 
• + ' j ^ l 
Improvement in the Collection and Preparation of the 
Caoutchouc . 
Improvements should be effected in the collection and preparation 
of the Caoutchouc of the Ficus elastica. The time of year at 
which the milk sap ascends to the flowers has an effect on the 
quantity of Caoutchouc yielded. At the time of flowering of the 
Heveas scarcely any milk can be obtained from the trunk, 
whereas the panicles if cut, yield it in large drops. If a tree be 
tapped too often, without a sufficient period of rest being allowed 
to intervene between each successive operation, each successive 
yield is less rich in Caoutchouc and more watery and the tree 
itself becomes permanently injured. In the wet season there is a 
larger per-centage of water in the milk than in the dry season, and 
therefore the collection is not so profitable. The time best suited 
in Assam, Mr. Mann finds to be Eebruary, March, and April. 
After tapping, a period of at least three years should elapse before 
the operation is repeated in order to allow the tree to recover its 
strength. Judicious tapping does not injure a tree nor check its 
growth, but the danger lies in over-tapping or bleeding to death. 
Natives always resort to over-tapping if left to themselves. This 
