AGRICULTURAL BULLETIN 
OF THE' 
STRAITS 
ANIJ 
FEDERATED MALAY STATES. 
No. 12.] DECEMBER, 1906. [VOL. V. 
THE SECOND ANNUAL REPORT 
ON THE 
Experimental Tapping of Para Rubber 
Trees in the Botanic Gardens, 
Singapore, 
FOR THE YEAR 1905. 
The Experimental research into the yield of latex and caoutchouc, 
the growth of trees and other points of importance bearing on the 
cultivation of Para Rubber trees Was continued during the year. 
A clerk and from six to ten men were employed in the work, and 
their wages, the rebuilding of the drying house, and the necessary 
tools and chemicals for the work, were paid for out of the money 
obtained by the sale of the rubber prepared during the experiments 
as in the previous year. Though the price of rubber had fallen 
from 6/9 d. per pound to 6/2^., the increased amount of rubber 
obtained, 1,110 lbs., as against 884 lbs., more than compensated 
for this fall. 
The General Plan of the Research. 
For the purpose of the experiments the same trees were used in 
1905 as in 1904, but the experiments were modified both in method 
and in the periods of tapping. The spiral method of tapping so 
highly spoken of in Ceylon was experimented with, and the results 
are treated of separately, but as far as the series of experiments first 
to be detailed are concerned the herring-bone system only wasadopted, 
and with it experiments in variation in yield due to evening and 
morning tappings, single and full incisions, and tapping every day 
and on alternate days were carried out. Investigations into the 
effects of tapping throughout the year, and to show whether the 
same groups of trees could be tapped more than once in the year 
without inflicting any injury on them were also carried out. For 
