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 

 proportionately increase; besides if there is any considerable 

 drop in the pries 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. ENDUCH '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 



W. J. GALLAGHER. 



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 

 tw o most popular methods in use in Malaya at present are the V 

 an d the herring-bone. It is objected however to the former that so 

 n>any CU ps are required. The latter is frequently to be seen 

 ae Precated on account of the central channel which is a mere 



inductor of latex, being unproductive in itself and wasteful of 

 cortex. I t is said also that it lessens the tension D f the bark and 



nerefore tends to minimise the output of rubber. If such is so with 

 "> e lull herring-bone, how much more proportionately is the vertical 



nannel uneconomical in the case of the half-herring-bone! 



Examining recently a series of trees tapped by the latter method 

 " appeared to me that if the length and position of the conducting 



nannel were somewhat altered it could be made both productive of 



