Gums, Resins, 



2 



[July, 1908: 



GUMS, RESINS, SAPS AND EXUDATIONS. 



PROGRESS OP THE RUBBER 

 INDUSTRY IN TRINIDAD. 



By J. H, Hart, f.l.s., 

 Superintendent, Royal Botanic Gardens, 

 Trinidad. 



At the West Indian Conference of 1901, 

 I read a short paper on the experiments 

 carried out by the Botanical Depart- 

 ment, Trinidad, in connection with the 

 cultivation of various kinds of rubber 

 trees. In that paper (published in the 

 West Indian Bulletin, Vol. II., pp. 100-10), 

 six different kiuds were mentioned, 

 viz., Castilloa, Hevea, Manihot, Ficus, 

 Landolphia, and Puntumia ; to which 

 was also added Balata (Mimusops glo- 

 bosa), a native tree affording produce 

 similar to that of guttaperchas of the 

 East. 



Castilloa or Central American 

 Rubber, 



Since 1901, Castilloa planting has 

 been steadily continued in Trinidad, and 

 some thirty-three estates are now en- 

 gaged in the industry, the total number 

 of trees planted being estimated at 

 some 800,000. Numerous experiments 

 have been made with a view to discover- 

 ing suitable methods of tapping and pre- 

 paring the latex, and the specimens 

 secured afford reliable evidence of the 

 success achieved. 



It can now be recorded that the colony 

 of Trinidad and Tobago have several 

 plantations which, during the past year, 

 marketed rubber of fine quality and ob- 

 tained satisfactory prices. In recent 

 account sales, 3s. 3d. was obtained from 

 Scrap and 4s. 3d. from Castilloa Sheet rub- 

 ber. The samples were identical with 

 those presented at the Conference. In 

 Tobago, fine rubber has been produced. 

 Scrap realized 4s. per lb., while prepared 

 Sheet made Is. to Is. 3d. higher. The 

 quality of this rubber may be judged 

 from the produce kindly loaned by pro- 

 prietors, now exhibited. 



In Mr. de VerteiuTs block rubber we 

 have a very fine specimen, and I should 

 not be surprised to find rubber prepared 

 by this method taking a first place upon 

 the market, it being apparently pre- 

 ferred to sheet on account of its oxidizing 

 less quickly. 



The specimens of Castilloa prepared by 

 the Experiment .Station show the result 

 of experiments in preparation. 



The first was prepared by creaming in 

 three waters- and 'then naturally coa- 



gulating by placing in blotting paper 

 over a fine wire strainer. 



In preparing the second specimen, the 

 rubber latex was washed through a fine 

 strainer with about eight volumes of 

 water and then left for six days. The 

 rubber naturally coagulated on the 

 surface in a solid mass, and has since 

 been pressed and dried. 



The third specimen is the creamed 

 latex of the first sample pressed between 

 blotting paper, the fibre of which has 

 formed a coat upon the surface. This is 

 seen to have preserved the specimen 

 from oxidization, except in places where 

 it is not covered with the paper fibre. 



The rubber latex from which these 

 specimens were prepared was produced 

 by immature and undersized trees about 

 eight and a half years old, which were 

 cut out for thinning purposes. The 

 rubber is not of first-class quality, but 

 the specimen prepared without washing 

 appears to be the best and most elastic. 



The 'Tortuga' sample is from trees 

 some nineteen years old. The 'Louis 

 D'Or ' sample is from younger trees. 

 The ' Richmond ' sample is from trees 

 some twelve to fourteen years old ; the 

 exact age of the trees is not stated, but 

 it is mentioned that 4 lb. of dry rubber 

 is expected from one of the trees for the 

 year 1900. 



The ' Monte Christo ' sample is from 

 one of the first estates planted witii 

 this kind in Trinidad. The age of the 

 trees which produced it is not stated by 

 the proprietor, but from certain facts 

 known to me I assume it to be nineteen 

 years. 



The ' Verdant Vale ' sample is from 

 young trees seven and a halt-years old. 

 It appears that scrap rubber of the 

 quality seen on the table is readily 

 saleable, and as it costs less to prepare, 

 it raises a question whether the price 

 realized for sheet rubber is sufficient 

 to cover the cost of extra preparation. 



The cost of preparation per lb. has 

 been variously estimated. It would 

 be unsatisfactory, however, to make a 

 definite statement of the cost of tapping 

 and preparation oc the present evidence. 

 One large grower states that he prepares 

 his sheet rubber by indentured labour, 

 at the rate of 15c per lb., but whether 

 this will prove generally above or below 

 the average is still doubtful. In my 

 estimates I fix the cost of preparing 

 sheet rubber at a somewhat higher 



