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Reduced to 1 M 2 of tapped surface, then tree No, 14 seems to be 
a better rubber-producer than tree No. 9. 
No. 14 gave, rather should have given, 1334 and No. 9, 850 
grammes of rubber per M 2 of tapped surface. 
The individual differences in the product of latex given by the 
above methods of tapping are clearly shewn by the results of the 
first year's tapping of two 24-year old trees growing next to each 
other and tapped at the same time and by the same methods. 
Tree No. 10 was tapped over a surface of 4*5 M 2 and tree No. 
11 of 3*35 M2. 
The yield was, respectively, 380 and 608 grammes or 84*4 and 
181*5 grammes per M 2 - 
Tree No. 11 yielded more than twice the quantity of rubber, not- 
withstanding that the other was tapped over greater surface. 
From these experiments we may conclude that there exists a great 
deal of individual difference in the yield of rubber amongst the trees 
cultivated in the Gardens. 
These trees are also different in their forms. The best rubber 
producer is compact, has a thick crown and leaves of which the 
length and breadth are nearly equal, while the crown of the other is 
wider and the leaves are longer. 
In the first year of tapping, the influence of the season is also 
apparent. 
Tree No. 2 was tapped in August (the dry season) and again in 
November. The yield was, respectively, 41 1 and 390 grammes per 
2*79 M 2 of tapped surface or, per M 2 » respectively, 147-3 and 139*8 
grammes. 
This shews that the difference in this case was not large. It may 
be noted that the East Monsoon was drier than the West Monsoon 
but not much, however, as may be seen from the Rain-tables. 
In the dry season there were, during the time of tapping, 6 rainy 
days with 148 m.m. of rain, while during the wet season, these figures 
were 13 and 165. 
If the humidity of the soil is large* and if the rains are equally 
distributed during the tapping season, then there ought to be no 
large difference between the yield of the wet and dry seasons. + 
We shall have the opportunity of following these results for con- 
secutive years. From the above results, we may also reduce that 
full grown trees may, according to our system, be tapped twice a 
year. 
The second year will shew how far an increase of the number of 
incisions increases the yield of the rubber. 
* In our case we have to deal with clayey soil. 
t Large differences are caused in cases where fafctors that cause drying, such as a 
clear sky, much sun and wind, are acting during the tapping. Of this, we have been 
able to amply satisfy ourselves, and for that reason the trees are tapped as early as 
possible in the morning and tapping is not continued longer than till io A M; 
