RUBBER PLANTING 77 



longer intervals. In illustration of this difference, details 

 are here given of the yields during the first four months 

 of 1912. 



TABLE XVIII 



Yield of dry rubber \ January to April, 1912. 



Row 



II. III. IV. V. VI. VII. 



Number of tappings 42 32 24 20 16 14 

 Yield of dry rubber 



(grammes) ... 3,164 2,216 3,873 4,072 3,765 2,862 

 Yield per tapping 



(grammes) ... 75 70 161 203 235 202 



The above figures may be compared with those in 

 Table XI. A more convenient comparison is given 

 however in the following table. 







TABLE XIX 

 Yields in grammes per inch of circumference. 



Average Average yield per Average yield per 



tapping tapping per inch tapping per inch 



interval of bark, ist 40 Jan. Apr., 1912 Diflfer- 



Row (days) tappings (grms.) (grammes) ence 



II. 2*6 *34 *2i *I3 



III. 3-9 -49 -22 --27 



IV. 5-1 -44 -44 o 



V. 6-5 -50 -60 -io 



VI. 7-8 -48 -58 -io 

 VII. 9-0 -37 -51 -14 



It is to be observed that January to April is usually 

 a period of comparatively low yield, whilst the first 40 

 tappings of groups V, VI and VII extended over the 

 whole of the period of highest yield. The increase in 



