460 
Experiment V. 
A most interesting experiment confirming the necessity of an 
interval of rest of six months, and the advantage of morning over 
evening tappings as while the former represent the second period 
of tapping and the yield of latex less, the ratio of caoutchouc was 
greater, and it may be noticed that the morning tappings included 
80 trees tapped by single incisions. The average yield per tree 
per annum including scrap was 1 lb. [3 ozs. 
Experiment VI. 
According to the synop as of this experiment daily tappings 
shew a better result than alternate days. The poor return during 
November, December, 1905, and January, 1906, or first period of 
tapping within a year may be partly explained bv recalling 
that the heaviest fruit crop recorded terminated in December, the 
heavy fruit crop and tapping period being conterminous. The 
whole group ob trees therefore, was uniformly dormant. Despite 
this fall-off the trees average 3^ lbs. gross. 
Summary. 
The great problem involved in the scientific cultivation of rubber 
trees is briefly how to obtain the largest amount of rubber at the 
cost of the least injury to the tree, and the least damage to the 
bark. This result depends mainly on three points, viz : — 
(a) the use of the most suitable tapping knife or other imple- 
ment for making the incisions 
(b) the selection of the best season or seasons, and time for 
tapping 
(c) and the system which allows of the most rapid wound 
recovery. 
Tapping Implements. 
The kind of instrument used has a direct bearing on the actual 
flow of latex. Ffoiu observations of the effects of incisions made 
by various implements, we are convinced that the tree responds 
to shock and the implement capable of making the cleanest and 
quickest incision is the ideal one. 
This we have found in an English pattern obtainable in Singa- 
pore, it is a modified farrier’s blade adjusted by a screw in a sliding 
socket and can be fixed at different angles as desired. It is 
substantial and makes a grooved incision, thus forming an excellent 
channel and saving drip, and is equally good for all methods of 
tapping. 
Nearly all other invented knives or tools have been experimented 
with at the Botanic Gardens, some have been found unhandy, others 
unsuited for coolie use, and some much too fragile. 
