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of dry rubber per tree from 311 trees in one year, The age of 

 these trees varied from 10 to 15 years, and the trees varied in cir-- 

 cumference from 30 to 70 inches at a yard from the ground. 

 These trees were tapped on the full herring-bone system ; the 

 tapping area covered half the tree and extended from the base to 

 a height of seven feet. The tapping was done very carefully, the 

 distance of seven feet being worked through in 240 days of con- 

 tinuous tapping. The yield from these particular trees will pro- 

 bably be increased by a change in the method of tapping and 

 tapping instruments during the current year. On a third Matabele 

 estate the Para rubber is inter-planted among cocoa the cocoa is 

 planted 12 by 12 feet, and the rubber through alternate lines of 

 cocoa, 24 by 12 feet. By the V method of tapping a yield of 3 lb. 

 of dry rubber from each of 10,000 trees is expected during the 

 present year, the trees being 8 to 15 years old. On this estate 

 several encouraging experiments in tapping from 6 feet upwards 

 to a height of 15 feet have been made, light ladders being used 

 for the purpose. 



The Province of Uva. "The most successful results at high 

 elevations in Ceylon have probably been obtained in the Province 

 of Uva. On Passara Group estate, Passara, Para rubber is being 

 cultivated up to and over 3,000 feet above sea-level. The trees 

 are of various ages, and one specimen, 13 years old, measures 54 

 inches in circumference a yard from the ground, and 60 to 70 feet 

 in height, though growing at an elevation of about 2,600 feet. 

 Tapping is being carried on with promising results up to 2,8oo feet, 

 and from the trees at an elevation of 2,6oo feet, varying in age 

 from 7 to 13 years, an average yield of 2 lb. of dry rubber per 

 tree was obtained during 1905. 



South Ceylon : Kahitara, Awbalangoda, Rayigam, &c. — "In the 

 South of Ceylon equally good and often better results have been 

 obtained. On one estate, 8,731 trees, having a minimum circum- 

 ference of twenty inches, gave in one year, an average of 1 . 72 lb. 

 of dry rubber per tree ... A section of another rubber property 

 in the South of Ceylon has given, from ll-year-old trees, the 

 average circumference of which is 30 inches only, no less than 

 5J lb. of dry rubber from each of 255 trees."' 



COAGULATION. 



"If* the pure latex is allowed to stand in a receptacle, it 

 finally coagulates and the caoutchouc globules with other sub- 

 stances float to the top, leaving a more or less clear liquid behind. 

 By the addition of chemical reagents or by subjecting the latex to 

 different temperatures coagulation may he hastened or retarded. 

 The coagulated substance after washing, pressing, and drying is 

 ultimately known as the rubber of commerce. In the production 

 of rubber from latex the planter may either take advantage of the 

 presence of coagulable constituents in the latex or adopt chemical 

 and mechanical means for the separation of the caoutchouc 

 globules from the rest of the latex . . . 



* H. Wright, Para Kubber. 



