A FORTNIGHTLY REVIEW 



OF THK 



IMPERIAL DEPARTMENT OF AGRICULTURE FOR THE WEST INDIES. 



— HBR^ 



NEW "S 



B«)TAN 



(iARU 



Vol. IX. No. 221. 



BARBADOS, OCTOBER 15, 1910. 



Pricb Id. 



CONTENTS. 



Page 



Ammonia, Direct Produc- 

 tion of 335 



Arrowroot (Nfw Markets) 

 Ordiiiancu, St . Vincent 329 



Banana Meal 3.S1 



Cacao, Production of, in 



1909 324 



Ca.ssava in Ceylon, Cultiva- 

 tion and Uses 329 



Concrete Posts on Estates 323 

 Cotton Notes : — 



Cotton Experiments in 



theXransvaal 32(; 



Cotton Exports from 



St. Vincent 326 



Cotton-Growing in Egypt .32G 



East African Cotton 

 West Indian Cotton ... 



Department News 



Departmental Reports ... 



Fungus Notes : — 



Some Diseases of Rub- 

 ber Trees, Part III ... 



Gleanings 



32e 

 326 

 331 

 327 



334 

 332 



Page. 



Green Manures for Wot 



Lands 325 



Grow th of Knowledge Con- 

 cerning Soil Fertility 321 

 In.sect Notes : — 



Some Pests of Cac lo in 



•Jamaica 330 



Market Reports 336 



Notes and Comments ... 328 

 Oil Seed Crushing Industry 



of M.irseillcs. 1909 .." 331 

 Oils, Essential, New ... 329 

 Paper, IManufacture of 



from Megass .325 



for 



Potatos Irish, Material 



Planting 



Rice, Manuring of ... 

 Rubber, Supply of t 



■Japan 



Students' Corner ... 

 Tuiks and Caicos Islands, 



Trade of .328 



Venezuela, British West 

 Indian Tradewith, 1908 335 



... 335 

 ... 328 



... 329 

 ... 333 



The Growth of Knowledge 

 Connernins Soil Fertilitv. 



jEVERAL editorial articles have been given 

 [in the current volume of the Agricultural 

 I News*, which have dealt with subjects relating 

 to the fertility of the soil. This matter is naturally of 

 first importance to the agriculturist, whether he 

 obtains his means of subsistence from the soil, or 

 whether he is in the position of an adviser to those who 



♦Pages 17, 33, 193 and 289. 



do this. This is probably one of the reasons why the 

 opening address in the agricultural sub-section of the 

 British Association, this year, by A. D. Hall, M A.F.R.S., 

 Chairman of the .Sub-section, dealt intimately with 

 matters relating to this subject, more especially from 

 an historical point of view. The main points brought 

 out in this address are of sufficient interest to merit 

 a recapitulation of them here. 



It was pointed out, first of all, that the fertility 

 of the soil was intended to signify the povver which 

 a piece of land possesses of producing crops, under cultiv- 

 ation. In the seventeenth century, which may be 

 regarded as the time of the commencement of organized 

 science, two important questions relating to this were 

 receiving the attention of certain investigators. These 

 asked for the causes of the increase in size of plants, 

 and for knowledge concerning the share which the soil 

 takes, in supplying material for such growth. The 

 first recorded experiment devised to gain the information 

 was made by van Helmont; in this,a willow tree weighing 

 .') lb. wa.s planted in 200 lb. of dried earth, contained in 

 a tub. On weighing the tree, after it had been grow- 

 ing in the tub for five years, it was found to have 

 increased to 169 lb. 8 oz., while the redried soil only 

 weighed 2 oz. less than it did at the beginning of the 

 experiment. The conclusion obtained from the investig- 

 ations was that water had been transformed into 

 the material composing the tree, and this idea 

 was upheld by Boyle, who grew pumpkins and 

 cucumbers in weighed earth, and, going further, 

 distilled the plants that he obtained, thus getting 

 from them various tars and oils, charcoal and ash. 

 There were at the same time, however, those who paid 

 attention to the fact that spring water contains dis- 

 solved material which might assist in the growth of the 



