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was the opinion of Carlos Berger, but are irregularly arranged, 

 the tapering end of one fibre fitting between other fibres. When 

 the fibres are cut across by a tapping instrument their content is 

 ejected by bark pressure. Such a cut will take latex from the 

 tree only for a distance of 3 or 4 inches each side of the cut. This 

 shows that the latex does not run up and down the tree or from 

 one fibre to another. If no more cuts are made, the latex will not 

 be renewed in the cut fibre for some time (not entirely for about 3 

 months), although the surrounding fibres are full of latex. This 

 shows that all the latex from the tree cannot be taken from one 

 cut. 



The distance apart that cuts should be made around the tree is 

 a disputed subject, and depends not only on the length of the bast 

 fibres and the way to get the most yield, but also on the amount of 

 injury done to the tree. If yield were the only consideration, one 

 foot would be a good distance and would give, I believe, the 

 maximum yield. Eighteen inches will give close to the maximum, 

 giving enough more latex from each cut to make up for the fewer 

 cuts. Both of these distances, however, are objectionable, because 

 a large number of cuts appears to detract from the healing powers 

 of the tree, and the more cuts, the greater the chances of the tree 

 being injured by the borer. Another point in the number of cuts 

 is the time and labour in making the cuts. Six cuts to a tree is 

 twice as much labour as 3 cuts, but if it does not give twice as 

 much rubber it would be cheaper to make 3 cuts and tap a larger 

 number of trees in a day. 



The tapping is now being done with only 3 cuts per tree ; one 

 at the base, one at 5 feet from the ground, and one halfway 

 between these. Tapping above 5 feet necessitates the use of lad- 

 ders, and this would mean' more labour and would hardly pay 

 with young trees. I believe the making of 4 cuts, the top one 6 

 feet from the ground, would give enough more than 3 cuts to pay, 

 if it is not too great an injury to the tree. 



The first signs of healing appear between one and two weeks 

 after the cut is made, and in two months at the latest the cut is 

 well healed. In time the old cut will fill with new material which 

 contains latex and can be tapped again if necessary. Another 

 strong reason why the tool should cut to the cambium is that not 

 only does the shallow cut miss cutting some " milk tubes" but it 

 misses a very large proportion of the tubes. The milk tubes are 

 formed by the cambium in layers. The ones closest to the outside 

 bark were formed when the tree was very young and small in cir- 

 cumference. At that time the patches of tubes were'close together. 

 Since then the same number of tubes had to spread out and cover 

 a circumference of, say 18 or 20 inches. The spaces between 

 these tubes are filled by medullary rays which run from the pith 

 outward through the wood to the outside bark. Therefore the out- 

 ermost layers contain very few milk tubes, the next more, and so 

 on, until the innermost layer has the most since it was formed 

 when the circumference was greatest. This is borne out in facts. 



