OD^ 



THE INDIA RUBBER WORLD 



[June 1, 1917. 



service They claim that this service should be maintained and 

 supported, and point out that though delays occur, it is a con- 

 venience where speedy delivery is not essential. When, how- 

 ever, papers publish letters signed by a number of merchants of 

 the Acre region, in which it is declared that radiograms intended 

 to advise the dates on which vessels from Belem or Manaos are 

 due at certain ports, arrive later than the boats, one is inclined 

 to question the practical value of this vaunted convenience. 



PLANTATION RUBBER IN BRITISH GUIANA. 



THE rubber-planting industry of British Guiana is progressing 

 slowly but steadily, despite the many disappointments 

 usually experienced in new ventures in tropical agriculture. Re- 

 ports from inspectors at various rubber-producing centers show 

 that farmers and planters have extended their areas under 

 Heiea and are continuing to do so. In some cases, however, 

 small areas had to be abandoned owing to the unfitness of the 

 soil for its cultivation; also certain areas planted with Sapium 

 rubber were discontinued. This accounts for the fact that the 

 final totals of the 1915 report show a small decrease in acreage. 



PLANTED .ACREAGE. 



The following figures are interesting as illustrating the general 



growth of the industry for the period 1910-15. 



Areas Under Rubber. 

 aJ ^ 



1910. 1913. 1914. 1915. 



Demerara acres 579 1,859 2,196 2.229 



E=sequibo 1,129 2,142 2,206 1,854 



Berbice 30 501 560 603 



Totats 1,738 4.502 4,962 4,686 



• The report from the Botanic Gardens, Georgetown, stated that 

 ' no foreign seeds had been imported in 1915, as there had been 

 sufficient local seed to meet the demand for plants. Altogether, 

 21.846 plants were sold during that year. 

 RAINFALL. 

 The total rainfall lor 1915 was satisfactory, having been 9.53 

 inches more than m 1914. 



The following table, taken from the 1915 Report of the De- 

 partment of Science and Agriculture, gives the rainfall over S3 

 years : 



Rainfall at Georgetown and 



Period. Tanuarv. February. March. .■\pril. May. 



1846-1856 " 6.84 5.82 7.25 7.41 14 05 



1874-1879 6.55 3.58 5.59 6.39 12.58 



lSSO-1889 6.48 6.67 4.57 6.52 11.44 



1890 1899 11.52 8.0S 8.19 7.31 11.08 



1900-1909 7.61 5.87 9.43 7.8.> 12 30 



1910 8.09 7.95 lO.OO 7.86 10 81 



1911 10.17 9.13 14.04 8.43 11.13 



1912 1.23 .46 1.28 6.26 9.0S 



1913 18,18 2.41 7.64 2.09 5.00 



1914 : 1.79 2.46 2.34 4.22 18.37 



1915 6.41 13.38 .95 5.73 17.65 



Means (53 ye.nrs) 7.63 5.99 6.94 7.00 i:.27 



DISEASES AND PESTS. 



The plantations suffered to a certain extent from diseases, 

 the South .-Vmerican leaf disease (Fusicladium macrosporum) 

 having been the most prevalent.. Brown root disease (Hymeno- 

 chaete noxia) and die-bark (Thyridaria tarda) also attacked 

 the trees. Root disease {Fames sanitostus) , well known in the 

 East, was observed here for the first time. 



Fortunately no new serious insect pests were remarked at 

 the Government Rubber Station, Issorora, N. W. D., a species 

 of Coushi ant [Atta (Acromyrmex) octospina, Reich] was seen 

 removing and carrying away material from the layer of tissue 

 immediately overlying the cambium of recently tapped trees, 

 causing considerable damage to some trees. This ant has not 

 been met with in other parts of the colony. 



Disease has kept away from the Government Farm, Onder- 

 neeming, in quite a remarkable manner, consequently the Heveas 

 there are in good condition. The accompanying table shows 



the yields of experimental tapping of 200 trees averaging seven 



years of age. 



Number of Dry Rubber. Rainfall. 



1915. Tappings, Ounces. Inches. 



August 21 AZOyi 2.64 



September 30 744H 2.95 



October 31 864 1.82 



November 27 873 7.68 



December 27 975 5i 8.32 



Taking the four completed months September to December the yield has 

 been 3,457 ounces, equal to, say, 216 pounds, or 648 pounds for 12 months, 

 showing a yield of 3J4 pounds per tree per annum. 



BALATA. 



Several bullet tree seedings of balata, found growing in the 

 forest behind this station, were dug up and planted in the culti- 

 vation in 1511. These trees reached a height of 18 feet during 

 the four years from 1911-1915 and are in good condition. 



In connection with balata, it is interesting to learn that ex- 

 periments to determine the composition of Guiana balata, about 

 wliich little appears to have been reported, were conducted at 

 the Government Laboratory. Samples from British and Dutch 

 Guiana were submitted to analysis, determinations being made 

 of moisture, resin, crude proteids, other vegetable impurities, 

 tnineral matters and gutta. It was found that in the British 

 Guiana samples water varied from 2.5 to 7.1 per cent, resin 

 from 36.4 to 39.6 per cent, crude proteids from 2.6 to 6.3 per 

 cent and other vegetable impurities from 4.2 to 11.7 per cent, 

 mineral matters from .5 to 1.1 per cent, whilst the valuable con- 

 stituent, the gutta, varied from 40.1 to 52.1 per cent. From the 

 results of the examinations coupled with the history of the sam- 

 ples it was deduced that normal British Guiana balata should 

 contain 45 per cent of gutta and 38 per cent of resin, any pro- 

 portion of the latter above 38 per cent being regarded as an 

 impurity. It was assumed that on the water-free basis less than 

 44 per cent of gutta, or resin in excess of 42 per cent, or 

 total impurities in excess of 15 per cent, indicates, as the case 

 may be, either low-grade balata, such as dabray bottoms, or 

 admixture with latex other than- that of true balata. 



A FRENCH COLONIAL CONGRESS, 



.\ colonial congress, organized by tlie Union Coloniale Fran- 

 caise and aiming to bring the home manufacturer in closer 

 touch with the colonial producer, is being held at Paris this 

 month. 



A special section devoted to rubber is presided over by M. 

 Jumelle, professor of the Faculty of Sciences of Marseilles, He 

 has distributed among those interested a circular requesting re- 

 plies to such questions as : 



(1) In what proportion can wild rubbers from Africa, America 

 (not Para), Tonkin and Java, be used in rubber factories? 



(2) What kinds are the most satisfactory? 



(3) How does Brazilian rubber differ (from an industrial 

 viewpoint) from Ceylon or Malayan plantation rubber? 



(4) Which of the three plantation rubbers — Ceylon, 'Malay 

 Peninsula, Java — is to be preferred? 



(5) What form — crepes, biscuits, blocks — is preferred? 



(6) How does Cochin China rubber compare with other planta- 

 tion rubbers; also the value attached to Ceara, Funtumia and 

 Castilloa plantation rubber from French colonies as compared 

 with that from other countries? 



The result of the questionary will doubtless prove valuable. 



