A FORTNIGHTLY REVIEW 



OF THE 



IMPERIAL DEPARTMENT OF AGRICULTURE FOR THE WEST INDIES. 



Vol. XV. No. 359. 



BARBADOS, JANUARY 29, 191 G 



Price Id. 



CONTENTS. 



Page. 



Antliiax ill Elephants ami 



Goats 



Agricultural Examinations 

 Bacon and Hams, Diy- 



Salting 



Bacon Factory, A Succes.^- 



ful " 



Birds, Domestication of 



Fancy Plumage 



Cheese-Cloth, Growing 



Plants under 



Cotton Notes: — 



Canons of the Cotton 

 Plant in Egypt 



West Indian Cotton ... 

 Cuba's Sugar Productitm, 



Possibilities of 



Department News 



Departmental Report.s 



(Jleanings 



Humidity and the (irowth 



of Croi)S 



Earth 



Page. 

 a 



Infusorial 



Manure 47 



Insect Notes: — 



D;ingerou.s Hard Backs 42 



Items of Local Interest... 30 



Market Reports 4H 



Notes and Comments ... 4(1 



Plant Diseases: — 



Wilt Disease of Sugar- 

 cane: A Correction ... 4() 



Queensland, Co-operati\e 

 Sugar Works in 40 



St Lucia Lime .Juice Fac- 

 tory 41 



Sugar Industry: — 



Studies in Indian Sugar- 

 canes .■-!4 



Surinam, Novel Schemes of 

 Instruction in 41 



Trinidad News .S7 



Yeast-Fodder 4(> 



Humidity and the Growth of Crops. 



' ECENT ob.servations have made it clearer 

 I than ever that the chief climatic fector 

 , regulating the d'stribution and growth of 

 crops in the West Indian island.s is humidity of the air. 

 'I'he degree of humidity does not necessarily vary with 

 the rainfall: the atmosphere in some parts of Grenada, 

 for instance, contains more moisture than that in some 

 parts of St. Vincent where the rainfall is higher. Humid- 

 ity in any situation depends upon the degi-ee of exposure, 

 the amount of forest growth, cloud protection from the 

 sun, and the water-holding capacity of the soil. Rain- 

 fall is the ultimate cause of humiility, but it is not the 

 unly regulating factor. 



In the issue of this .Journal for January IG, 191.5, 

 we published a short summary of a paper on the Gold 

 Goast Gacao Industry, read by the Director of Agricul- 

 ture of that Golony before the International Congi-ess 

 of Tropical Agriculture. The following extract, in its 

 bearing upon the subject of this article, occurs to us 

 as being well worth repetition: 'It is due to the 

 climate, more than to the soil, that the Gold Coast is 

 pre-eminently a cacao-growing country. The rainfall 

 is not excessive, but the humidity is high owing to the 

 wealth of vegetation. In fact the rainfall is actually- 

 lower than in any other cacao-growing country, and 

 a reduction in the humidity would be followed by 

 di.sastrous consequences. The natives are not fully 

 alive to the seriousness of the position, as the destruc- 

 tion of forest in making new clearings is being some- 

 what ruthlessly undertaken all over the country, and 

 a Bill, recently introduced by the Government, for the 

 regulation and preservation of the forests, is being 

 vigorously opposed by the native owners of the land.' 



This shows in an unmistakable manner the 

 importance of humidity in the cultivation of cacao, and. 

 it further points to the necessity of preserving forest 

 growth on the uncultivated areas. The protection of 

 forest is a matter that has been given careful consider- 

 ation in most of the Vk'est Indian islands. It cannot 

 be overstated that such tree growth has a very 

 important influence upon the atmosphere and soil 

 seepage: but it does not increase the rainfall: it 

 conserves the rainfall and increases the proportion of 

 water-vapour in the atmo.sphere. 



Limes and rubber, like cacao, require a moist 

 atmosphere. Exactly why, is a complicated question. 

 to answer, but it must be closely connected with 

 transpiration. Further, moisture seems necessary for 



