A FORTNIGHTLY REVIEW 



OF THB 



IMPERIAL DEPARTMENT OF AGRICULTURE FOR THE WEST INDIES. 



Vol. XII. No. 299. 



BARBADOS. OCTOBER 11. 1913. 



Price Id. 



CONTENTS. 



Page. 



Alcohol as a Motor Fuel 327 



Anonaceous Possibilities for 

 the Plant Breeder ... 324 



British Honduras, Opportu- 



■ nities for Planters in... 329 



Cacao, Ferinontation of... 321 



Cac;io, Shading and Manur- 

 ial Experiments with in 

 Ceylon 324 



Cane Juice, Clarification of 

 liy Electricity 325 



■Coco-nut Plantation, Cost of 

 Est.il.lishing 324 



Cotton Notes : — 



Cotton Problems in Lou- 

 isiana 326 



West Indian Cotton ... 326 



Fungus Notes : — 



Recent Japanese Work on 

 Entomogcnous Fungi... 334 

 Contamination of the Soil 

 by the Toxic Products of 

 Parasitic Fungi 334 



Future of Tropical Ameri- 

 ca 328 



Gleanings 332 



Insect Notes : — 



How Ticks are Killed in 

 the Dipping of Cattle... 330 

 Millions, Successful Trans- 

 poitation of, to the East 330 

 Sugar-cane Pests in 

 Queensland 330 



Page. 

 ... 326 



Kapok Industry 



Live Stock Notes: — 



Producing Wool in the 



Tro])ics 331 



Tulierculous Poultry the 

 Causo of Tuberculosis in 

 Pigs 331 



Market Reports 336 



Notes and Comments ... 328 



Periclinal Chimeras 329 



Pro})osLd College of Tropi- 

 cal Agriculture in Ceylon 329 



Rubber. Mechanical Extrac- 

 tion of 327 



Rabber Position, the ... 323 



Sclxi'ils for the Study of 

 Rubber 333 



Soil Inve.stigations: — 



Stdpliurin Relation to the 

 Manuring of Rice ... 33.5 

 Composition of Soil in the 



Virgin Islands 335 



Metliod of Estimating 

 Calcium Carbonate in tiie 

 Soil 335 



Students' Corner 333 



\'ai ieCies of Sugar-cane in 

 Tucuman, Argentina ... 334 



West Indies, Exports to 

 Canada, 1912-13 328 



World's Cane Sugar Indus- 

 try ^ 325 



The Fermentation of Cacao; A Review. 



'N bringing togetlier in liis recent book,* six 

 essays on the ferinentati'on of cacao, written 



J by experts of scientific eminence and prac- 

 tical experience, there can be no doubt that in one way 

 iSlr. Ilamel Smith has perfoiined a public service; 

 for he has very effectively shown the great want of 



*I7ie F- niieiitaliou of Cacao: wdited by Harold Hamel 

 Smith. Londim, 1913. 



co-ordination in estate practice, and the lack of scienti- 

 fic investigation into the exact nature of the changes 

 which take place during the plantation manufacture 

 of the important product under consideration. The 

 book is one which must attract attention. We feel, 

 however, that from the grower's point of view, the 

 work leaves something to be desired. Owing to the 

 controversial nature of the subject dealt with, the 

 book does not lead up directly to anything definite; 

 it cannot therefore be merely read, but must be 

 studied: points have to be taken separately and the 

 views of the various writers sought for; and, in summing 

 up these views and opinions, allowances have to be 

 made for variations in local conditions and the degree 

 of conclusiveness of the experiments or observations on 

 which these views are based. It is true that in the 

 last chapter entitled somewhat incongruously 'The Last 

 Word,' we are given able critiques by Dr. Fickendey 

 and others, but these, again, require sifting, and taking 

 everything into consideration one feels sadly the want 

 of the editor's guiding hand as one travels over the 

 tortuous ground towards some hoped-for destination. 



What is the fermentation of cacao? On one point 

 all the writers agree, namely, that the process must 

 be considered as consisting of two things. The first 

 is the conversion of the sugar in the pulp into 

 alcohol and then into acetic acid (vinegar), by means 

 of the action of yeasts and bacteria. The second part 

 of the process is not dispensed with quite so easily. As 

 a matter of fact it would seem better not to regard it 

 as a part of fermentation at all, but rather as the effect 

 of it. According to Loew, Fickendey, Schulte and 

 Sack, the second part of the change consists in the 

 killing of the embryo or germ in the cacao seed 

 through the heat evolved in the 'sweating', and the 

 consequent putting into action of enzymes already 

 within the nib. The action of these enzymes 



