359 



Saps and Exudations. 



resting with full weight upon itself. No inner lining of common paper or other 

 friable material should be used — such wrapping is bound to get broken in transport, 

 and particles of it work their way between the layers of rubber, and obstinately 

 adhere to the rubber. The first shipment of crepe rubber which I saw unpacked 

 had been enclosed in wooden cases with paper lining. When the folds of separate 

 layers of rubber were pulled apart, a shower of fine grit, particles of paper, 

 and dust was then thrown out from the rubber. This rubber, though well cleaned 

 and washed on the estate, would for fine work have required re-washing. The 

 separate sheets of crepe had adhered firmly into one solid mass, which 1'equired 

 a crowbar to separate into the original layers, and the whole had shrunk — 

 leaving a space of about an inch between the rubber and the sides of the case. 

 If any wrapping to prevent the intrusion of dust and grit be used, it should 

 be either smooth and strong, such as sheet zinc lining, or else made adherent to the 

 sides of the cases— as, for instance, strips of smooth paper pasted over the joints 

 in the Avood inside the cases. With less perfectly prepared rubber in biscuit, 

 or worm form, which will require Avashing before use, a less careful form of 

 packing might be adopted. It must be, of course, always remembered that the 

 rubber is valued by its appearance very largely, and uniformity in size and 

 colour of the sheets Avill have some influence in determining the price, though 

 really being no guide to the actual quality of the rubber." 



THE ALLEGED INFERIOR QUALITY OF PLANTATION RUBBER. 



Mr. Burgess spoke freely on this subject when he was in Ceylon ; and 

 he accepts the tests of home manufacturers as conclusive, although the late Dr. 

 Weber reported quite to the contrary. We, says the "Times of Ceylon," incline to 

 the belief that scientific research will supply an explanation, and, possibly, as the 

 trees grow older, the rubber will improve. It is known that the product of four- 

 year-old trees is inferior to that of eight-year-olds, and sixteen-year-old trees may 

 produce a superior article to eight-year-olds. We reproduce what Mr. Burgess says 

 as to possible causes. 



"The cause of the inferiority of plantation rubber, when compared with 

 pure South American Para rubber, is not known. Some of the manufacturers 

 believe it to be due to difference in the locality, climate and conditions under 

 which the trees are grown ; others incline to the belief that the difference in 

 quality is the result of difference in mode of curing and exporting, and again 

 the difference in age of tree from which the rubber is gathered may very 

 probably be the actual reason for the difference in quality of the rubber. 

 There is a further suggestion which has, I believe, never yet been made. The 

 rubber trees of South America which are tapped are selected, both by natural 

 and by artificial selection. The condition in South America is, I understand, one of 

 jungle in which the trees affect, and compete with one another ; and this leads to 

 the survival, by natural selection, of the finest and most sturdy only of the seedlings 

 The native in tapping selects the best of the trees he conveniently can, and here 

 the influence at work is one leading to the rejection of weak and badly-developed 

 trees. On the plantation, after the first selection of the stumps and seedlings, 

 no further selective process is actively at Avork. To determine Avhether this has any 

 influence on the quality of the rubber, tapping should be done on specially-se^t.^d 

 trees, and the quality of the rubber extracted compared with the average rubber 

 of that plot of trees. All opinions at present must be looked upon as guesses at 

 the solution of this question, the only thing certain is that plantation rubber is 

 inferior, and this certain knowledge is one of the most important results of my 

 visit to England. 



