Vol. XIII. No. 311. 



THE AGRICULTURAL NEWS. 



105 



West Indian Fibres and Rubber. 



The Reporb on the work of the Imperial Institute, 

 1912, contains information of considerable interest in 

 "the West Indies. A few facts are herewith abstracted. 

 During the year a sample of Aga-': americana fibre 

 from Antigua exhibited remarkable elasticity, elonga- 

 ting 30 to 40 per cent, of its orii^inal length before 

 breaking, and for this reason, commercial experts stated 

 that it would be of special value for the manufacture 

 ■of towing ropes. 



The investigation of the constituents of West 

 Indian satin wood {Zanthoxylum jfavuin) was com- 

 pleted. Two crxstalline substances and a number of 

 resins were obtained by extracting the sawdust success- 

 ively with light petroleum and alcuhol. 



From the Bahamas a consignment of two-ye.ar-old 

 stems of Cryptostegia grandifora were received and 

 found to contain only 0() per cent, caoutchouc, and it 

 was considered very doubtful if extraction of the rubber 

 bv solvents would pay. Para rubber from Dominica 

 contained 939 per cent, caoutchouc and was valued at 

 4s. 10'?. per ft. with fine hard Para at 4.?. ^\d. 

 A sample of Heuea confusa from British Guiana con- 

 tained 928 per cent, of caoutchouc and only I'S per 

 cent, of resin, but was deficient in physical properties. 

 It was valued at 4-s. per ft. in London with fine hard 

 Para at 4.9. sd. per ft. 



Agricultural Progress in Dominica. 



A copy has just been received of an address by 

 the Acting Administrator at a meeting of the Legis- 

 lative Council, Dominica, held on March 9, 1914. Those 

 portions of the address which concern agricultural 

 development are herewith abstracted. 



The value of the imports into Dominica has risen 

 from £148,977 in 1912 to £1.57,121 in 191-S, whilst 

 the exports have risen from £142,"i7:i to £174,30."). To 

 some extent the increase is due to the adoption of 

 a new method of assessing values; but the main cause 

 is the increase in the production of limes and lime 

 products, combined with the high prices which ruled for 

 these commodities. Calculated in barrels of fruit, the 

 crop for 1913 amounted to 39 1,1 -57 barrels — an inerease 

 of 21,157 barrels over the crop of 1912. The trade in 

 green limes continues to expand. The number of 

 barrels of fruit shipped was 43,832 — an increase of the 

 shipments during 1912 of 6,794 barrels. The satis- 

 factory returns per acre have been almost as great as 

 the prices, and the steady planting of lime seedlings 

 continues, it being estimated that about 300 acres are 

 established each year. 



Whereas the exports of cacao have shown 

 a decrease, there is every indication that the produc- 

 tion of coco-nuts, vanilla and grape fruit for export will 

 rapidly expand. In general, agricultural progress in 

 Dominica during 1913 may be .said to hare been 

 eminently satisfactory, principally on account of the 

 high prices ruling for lime products; and in future 

 years, even though these prices may not always 

 retain their present high level, the development of 

 important minor industries is bound to ensure a con- 

 tinuation of the Colony's advancement. 



Selection of Lands for Plantations in the 

 Tropics. 



A German writer has recently endeavoured to 

 arrange and classify the various factors which should 

 be considered in selecting land for planting purposes 

 in the Tropics. It is pointed out tirst that the 

 capability of land as regards cultivation is determined 

 in the first place by climatic conditions; within the 

 limit set by climate, the soil with its ecological and 

 geological factors becomes the decisive consideration. 



As regards the analysis of soils with a view to an 

 aid to selection, the writer gives a form for presenting 

 the results of mechanical analysis together with the 

 depth to which samples should be taken. The results 

 when expressed by the arrangement referred to present 

 a thorough description not only of the nature but the 

 extent and the economic value of the soil. For 

 instance, such matters as the depth at which rubble 

 is met with, the level of the water table and the price 

 or rent of the land are included. 



In the chemical analysis of the soil, the first step 

 is the investigation of the lime content. In general, 

 the writer believes that a tropical soil may be con- 

 sidered gooi] and suitable for a plantation from the 

 point of view of its capital in fertilizing substances, 

 when it contains: (soluble in cold hydrochloric acid) 

 lime + magnesia, 02 to 0'.5 per cent.; potash, phos- 

 phorous oxide, nitrogen, 01 p"r cent, respectively. 

 A form for chemical analysis of tropical soils is given. 

 This together with the one already referred to in 

 connexion with the mechanical analysis is reproduced 

 in the Monthly Bulletin 'if Agricultural rntelligence 

 and Plant Diseases (January 1914) from which the 

 information in this note has been abstracted. 



The determination of the absorbent power of the 

 soil is important, especially in connexion with the 

 prevalence in the Tropics of red and yellow soils 

 possessing a marked power of absorbing ammoniacal 

 nitrogen, and with the abundance of nitrogen in the 

 rainfall of the Tropics; thus a yearly rainfall of 

 120 inches brings down about 72 ft. of nitrogen to the 

 acre. The amount of nitrogen therefore brought 

 down in certain parts of Assam, for instance, which is 

 the wettest part in the world, and where the rainfall 

 is over 900 inches per annum, would be very con- 

 siderable. 



Turning to special crops, the kind of soils best 

 suited to the various tropical plants are described; with 

 this information most planters will be familiar, though 

 those who are not acquainted with the general soil 

 requirements of the principal tropica! crops will do 

 well to examine carefully the paper from which this 

 information has been obtained. 



The following are among some of the chief crops 

 dealt with : cacao, cotfee, nutmeg.?, vanilla, sisal hemp, 

 cotton, coco-nuts, oil and other palms, bananas, tobacco, 

 and provision crops. The employment of manures in 

 relation to the soils suited to the above crops is 

 discussed. 



