A FORTNIGHTLY REVIEW 



OF THE USi 



IMPERIAL DEPARTMENT OF AGRICULTURE FOR THE WEST INDIES ZZ 



Vol. XIII. Xo. 31-5. 



BARBADOS, MAY 23. 1914. 



Price Id, 



CONTENTS 



Page. 



Agricultural Education ... 165 

 Atemoya. A New Fruit for 

 the Tropics 164 



Balata in British Guiana 171 

 Biitish Guiana and Peasant 

 Agriculture 169 



Cacao, Practice of Fermen- 

 tation 175 



Canadian Tariff Changes, 



New 169 



Chickens and Bees ... 167 

 Clo\e Industry in Zanzibar 164 

 Coagulation and .Strength 171 

 Corii-Drj'ing Factory in An- 

 tigua, Opening of 162 



Cotton Notes: — 



Cotton- Growing in Queens- 

 land 166 



Studies in Indian Cotton 166 

 West Indian Cotton ... 166 



Dominica, 

 1913 



Exports 



from, 

 ... 168 



Page. 



Fibre-Cleaning Machine, 

 New 17:> 



Fungus Notes: — 



Two Tomato Diseases... 174 



Gleanings 172 



Hides and Skins for Export, 

 Preservation of 167 



Holding Black Cotton ... 175 



Insect Notes: — 



Insect Pests and Fungoid 

 Diseases in Barbados, 



170 

 169 



1912-13 



Is the Earth Drying up 

 Labour i>aving Devices, 

 Recent Progress in ... 173 



Market Reports 176 



Mauritius and Agricultural 



B.anks 163 



Notes and Comments ... 168 

 New Map of the West 



Indies, A 169 



Rice, Production of 168 



Sea Island Cotton, Manur- 

 ing nf 161 



The Manuring of Sea Island Cotton. 



^X the search for plant nutrients which 

 began early in the seventeenth century, it was 



(held by some that oil was the principle of 

 plant growth because it could be shown to contain 

 a large amount of carbon. This was long before 

 Liebig's famous report to the British Association 

 appeared — a report which established once and for all 

 that the plant's main, if not sole, source of carbon is the 

 carbonic acid gas of the atmosphere. The effect of this 

 discovery of the source of carbon has been very great 



as regards the question of manuring. We now 

 know that practically all plant products which, like 

 fi.xed oils, starches, fibres and sugars are composed of 

 carbon, hydrogen and oxygen, are valueless as direct 

 sources of plant nutrientsbecause they havebeenderived 

 from air. Hence in the cultivation of crops for certain 

 products, for instance the sugar-cane for sugar and the 

 cotton plant for lint, there would be no danger of dimin- 

 ishing the supply of plant food in the soil provided noth- 

 ing but these main products were removed. Unfortunate- 

 ly this is impossible, for the whole cane with its composite 

 ash is carried from the land, and the vegetative parts 

 of the cotton plant with its mineral content are also 

 removed. And not only in the cotton plant are the 

 vegetative parts — the stem, leaves and branches 

 removed — but also the seed, which, although it con- 

 tains a large quantity of oil, has within it also a con- 

 siderable amount of nitrogen, phosphoric acid and 

 potash, the three principal soil nutrients on which the 

 cotton plant, or any plant, depends for its successful 

 development. 



In view of the fact that the oil is useless for 

 manurial purposes, but, on the other hand, very valu- 

 able in the manufactures, planters have for some time 

 given consideration to the idea of expressing most of 

 the oil for shipment and turning the residues which con- 

 tain nitrogen and mineral ash (amongst other proximate 

 constituents) into cattle food for exportation. This, 

 however, at least in many parts of the West Indies, 

 does not seem to pay; and it has been a diffi- 

 cult problem to know how to deal economically with 

 this seed until the last year or two. Within this 

 recent period the cotton crops which have been 

 grown year after year on the same land have exhibited 



