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before from the top, and working downwards between the former rows, 

 A tree that will carry seven cups 8 inches apart is considered a large 

 one, and though trees that will carry eight or nine cups are to be met 

 with, the average do not carry more than four or five. 



It is not possible in the present state of the industry to give any 

 precise data as to the average yield of latex per tree. To begin 

 with, the trees are extremely irregular in their yield. Two trees 

 growing close together and under apparently precisely similar con- 

 ditions, will often vary very much as regards their yield of latex. 

 Some trees are very rapidly exhausted, whilst others have to be tapped 

 for some time before they yield the full amount of latex of which they 

 are capable. The natives account for this by saying that the tree has 

 to be accustomed to being tapped. Sufficient data are not available to 

 enable any judgment to be formed as to the correctness of this view. 

 It is certain, however, tliat even the most experienced cannot judge of 

 the value of a rubber estafe before at least a year's work has proven it. 

 The examination of the books of a number of rubber estates actually 

 working and from reliable information received, leads me to believe 

 that, for estates working with over 20 men, a yield of 300 kilos, per 

 annum per man may be expected should it be a good district ; 200 

 kilos, should the district be only fairly good ; and 100 kilos, per annum 

 per man should the estate be alreaiy overworked. As each man 

 works 200 trees, this would place the yield of one tree, when worked 

 under satisfactory conditions at 1 to IJ kilos, per annum. On the 

 same basis and taking the whole of the crop from the Amazon district 

 as being 24,000 tons (a .out) per annum, there would appear to be about 

 120,000 labourers employed in cutting rubber at present. Calculating 

 still on the same basis there should be some 24,000,000 trees being 

 tapped, and these on a basis of one tree to every 2 acres would give an 

 area of about 50,000,000 acres of forest at present being worked for 

 rubber. When it is considered that the district in question embraces 

 well over 1,000,000 square miles, and that it is by no means easy to 

 find virgin rubber forest within 200 or 300 miles of Para or Manaos, 

 it will be seen how comparatively scarce is the Hevea in the Amazonian 

 forests. 



The Hevea is found to yield its latex more freely at the base than 

 higher up the trunk. In some places, however, where the trees have 

 already been considerably worked, and the lower part of the trunk is 

 already covered with knobs due to excessive tapping, it is the custom 

 to build stagings in order to enable rubber-cutters to reach a higher 

 portion of the trunk. A good tree will still yield freely to a height of 

 ome 20 or 30 feet. 



If allowed to rest for three or four years, even a completely ex- 

 hausted tree will quite recover itself, and may be worked again from 

 the base As has been already stated, the tree is not killed when the 

 supply of latex runs short, and as a rule sufficient damage has not been 

 inflicted to prevent the tree from recovering itself. This fact is im- 

 portant, as owing to it the supply of rubber available will probably not 

 run short as has been often prophesied of late. Trees have been known 

 to have been tapped off and on during 50 years, and to be still yielding 

 .a plentiful supply of latex. 



