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protection of the stem by the growth of trees around it both in the 

 young and mature stage. He came to that conchision after a short 

 visit to Central America. I am of opinion that trees will grow at 

 50 per cent, greater rate if shaded than if not shaded, and if left 

 unshaded they will die : while those planted in the wood, as I can 

 show you on the lands of the Botanical Department, continue to 

 grow vigorously and scatter their seeds widely around. 



The President : Would you now discuss the question whether 

 Castilloa trees should be used as shade for cacao .'' 



Mr. Hart : Captain Short seems to be in favour of it, but it 

 seems to me that a a tree which itself requires to be shaded with 

 a tree equally its own height, would scarcely be of value as a 

 shade for such a low-growing tree as cacao, found indigenous in 

 Trinidad as a tree of the undergrowth of the forest. 



The President : Would not that vary with the climate as in 

 the case of cacao itself ? 



Mr. Hart : Probably ; but I am speaking entirely on Trinidad 

 and Central American experience. In Grenada, where shade is 

 not required, it is possible that Castilloa will grow equally as well 

 without shade as cacao now appears to do. 



With regard to tapping, the cultivation of rubber is yet in its 

 infancy, and the methods of extracting rubber are, up to the 

 present time, merely matters of experiment. We have tried ex- 

 periments with tapping rubber generally, and tapping at different 

 ages. These experiments have shown that the latex from young 

 trees contains a very much larger amount of resin, and that the 

 older the trees get, the larger the amount of rubber. In some in- 

 stances the rubber flows slowly and coagulates before it can run 

 down to the cup. In such cases it was probably tapped in dry 

 weather. After heavy showers the latex runs more freely and 

 contains much more water. I do not think that need interfere 

 with the operator because it is necessary to add a certain pro- 

 portion of water to the latex before you can clean it and prepare it 

 for perfect coagulation. The amount of rubber contained in the 

 ducts of different rubbers — Funtiimia elastica, Fiintumia africana, 

 Castilloa elastica, and others — has been well worked out by the 

 Chemists of the Imperial Institute, and the results are published in 

 Hnllctin No. 41, of the Botanical Department of Trinidad. A re- 

 cent issue of the Bulletin, for January 1905, contains a short article 

 on the preparation of Castilloa rubber. It is stated by other au- 

 thorities that the coagulation of rubber depends on the coagula- 

 tion of the albuminoids contained in the latex. Two or three 

 years ago I criticized that statement, and that criticism was adopt- 

 ed by the late Dr. Weber, then scientific adviser of the India Rub- 

 ber Association, and it has now been proved that we can remove 

 a large amount, if not all, of the albuminoids without injury to the 

 rubber. With regard to tapping, that, as I have said before, may 

 be regarded as being still in an experimental stage. It is believed 

 that more latex may be obtained from a horizontal than a vertical 

 cut. There is also the view held by Captain Short that an oblique 



