494 FETCH : 



per lb. In 1898 the same tree was again tapped. Seven full 

 herring-bone cnts were made with a chisel, and the latex was 

 collected in tins fastened to the tree mth a nail and clay. The 

 tree was tapped 15 times in 34 days, and 3 lb. of rubber was 

 obtained. Its girth was then 41 inches. The latex was 

 allowed to coagulate naturally except on two occasions, when 

 water got into the cups, alum being used in those cases. 



Curtis's reports for 1897 and 1898 contain the first recorded 

 observations on the phenomenon which is now known as 

 " wound response." In 1897 he pointed out the small yield 

 at the first incision and the subsequent increase^ in general 

 terms ; while in 1898 he recorded the separate yields for each 

 daj^'s tapping, showing an increase in yield up to the seventh 

 tapping. No other experimenter in the East had recorded 

 that previous^ — Ridley, for example, writing in 1897, does 

 not mention an5rthing of the kind ; and therefore whatever 

 credit is attached to the re-discovery of " wound response " 

 must be assigned to Curtis. 



In his 1899 report Curtis again referred to the necessity of 

 re-opening the wound, and- in 1900 he mentioned " smoke 

 drying," after coagulation. The Penang tree tapped by 

 Curtis was re-tapped annually until 1909, the total yield for 

 13 years being 52 lb. 6 oz. It is to be noted that this jdeld 

 is not comparable with yields obtained hj modern methods 

 of treatment, because in the earher years (up to 1904 ?) the latex 

 was allowed to coagulate naturally, and the rubber consequently 

 retained a high percentage of moisture ; Ridley states that 

 these earlier samples lost 35 to 40 per cent, on washing. 



In Januarj^ 1898, Willis issued a circular on Rubber Culti- 

 vation in Ceylon, dealing solely with Hevea. It was chiefly 

 a reprint of earlier records, but included the result of six 

 tappings, at weekly intervals, on 27 trees, about 2 feet in girth, 

 carried out in 1897 : the average yield per tree was a little 

 over 5 oz. The trees were tapped by separate V's, as in the 

 method employed by Trimen, and, as elsewhere at this date, 

 the latex was allowed to coagulate in the collecting cups. 

 Willis estimated that, with 300 trees to the acre, a yield of 

 120 to 140 lb. per acre might be expected after the tenth year, 

 with a prospect of a good return on the capital invested. 



