387 
price considerably, but it improved again and recently good qualities 
fetched as high as £0-2-3 per lb. in Hamburg. 
Exact details as to cost and profit per acre are not available, but 
at present prices Guayale is a profitable business. In some cases 
the raw material (plant) must be transported long distances on 
donkeys which adds considerably to its cost, and this factor will 
increase as the more accessible districts are completely exploited. 
The production per acre is variable and difficult to estimate on 
account of the very unequal sizes of individual plants; it has 
been stated to lie between 450 and 750 lbs. Further, while 
there are 15 factories working now there was only one actually 
at work in 1905, so that the primitive accessible supply must 
be quickly exhausted, and cost of production of raw material 
pr< portionately increase; besides if there is any considerable 
drop in the prices of Para, a demand for Guayale may not continue. 
The manager < f the Continental Rubber Co. in Mexico, estimates 
the present visible supply as sufficient for 7 years. The manager 
of the Company which has just been started to work the Guayale 
areas in Texas asserts that there are only about 10,000 tons of shrub 
available in the State. Dr. ENDLICH believes that no immediate 
danger threatens the Guayale industry, the second growth, he says, 
thrives often better than the first. Guayale, he says, offers a good 
opening to extract profit from desert-like districts, especially as a 
secondary industry in connection with ranching, and the plant may 
increase the value of similar comparatively unfertile areas in other 
countries. 
W. J. GALLAGHER.* 
TAPPING PATTERNS. 
THE “CHAIN-GAMMA.” 
The Editor, 
“ Agricultural Bulletin, ” 
Singapore. 
Dear Sir, — All methods of tapping rubber trees are, one may say, 
combinations or variations of the oblique incision and probably the 
two most popular methods in use in Malaya at present are the V 
and the herring-bone. It is objected however to the former that so 
many cups are required. The latter is frequently to be seen 
deprecated on account of the central channel which is a mere 
conductor of latex, being unproductive in itself and wasteful of 
cortex. It is said also that it lessens the tension of the bark and 
therefore tends to minimise the output of rubber. If such is so with 
the full herring-bone, how much more proportionately is the vertical 
channel uneconomical in the case of the half-herring-bone! 
Examining recently a series of trees tapped by the latter method 
it appeared to me that if the length and position of the conducting 
channel were somewhat altered it could be made both productive of 
