February 25, 1915] 



NATURE 



695 



of every employee in the establishment, to deter- 

 mine his physical condition and his fitness for his 

 special work" (p. 150). 



The subject of light and illumination in factories 

 receives careful treatment : " In Holland the law 

 requires a minimum intensity of 10 boug-ie-meters 

 (i foot-candle) to be maintained, and in some 

 special industries, such as sewang-, embroidery, 

 knitting;, printing", etc., an intensity of 15 boug-ie- 

 meters (i| foot-candles) is required " (p. 240). 



Employers welfare work is considered, and 

 incidentally " scientific management " is brought 

 under review : " The chief opposition to scientific 

 management in factories comes from the workers 

 themselves, from their representatives, and from 

 those social workers who dispassionately judge 

 this new efficiency movement in industrial produc- 

 tion " (p. 303). The example of an Enghsh manu- 

 facturing firm in employing a dentist to attend 

 to the teeth of their workers is recommended for 

 imitation. 



The chapter on " Air Ventilation in Factories " 

 includes forty-five pages and twenty-one illustra- 

 tions ; that on " Industrial Tests and Dusty 

 Trades," an equal number of pages and thirty- 

 seven illustrations. The illustrations in the chapter 

 on " Industrial Poisons, Gases, and Fumes," by 

 showing the intense discomfort of the necessary 

 preventive measures, enable the reader to realise 

 to a small extent the terrible dangers to which 

 the workers in certain industries are exposed. 



CACAO AND COCO-NUTS. 

 (i) Cocoa. By Dr. C. J. J. van Hall. Pp. xvi + 



515. (London: Macmillan and Co., Ltd., 



1914.) Price 14.S. net. 

 (2) The Coco-Nut. By Prof. E. B. Copeland. 



Pp. xiv + 212. (London: Macmillan and Co., 



Ltd., 1914.) Price 105. net. 



THESE two volumes form notable additions 

 to the literature of economic botany, and 

 will be w'elcomed alike by planters and depart- 

 mental officials. (i) For some years past the 

 cacao planter has been tolerably well provided 

 with useful handbooks, and an extensive and im- 

 portant literature has arisen in regard to special 

 aspects of his industry. Dr. van Hall's task, 

 therefore, has been undertaken with considerable 

 initial advantage, but with a special opportunity 

 of sifting the evidence now available and affording 

 an authoritative summing-up. Few are better 

 qualified for this task than the author, and the 

 present volume unquestionably affords the best 

 available discussion of the principles underlying 

 the successful cultivation of cacao. The arrange- 

 ment of the book follows established lines. Chap- 

 ters on the history, chemistry, and botany of 



Theobroma Cacao are succeeded by a discussion 

 of methods of cultivation, fermentation, and pre- 

 paration for the market, and treatment of pests 

 and diseases; there is, moreover, an admirable 

 account of the varying methods of cultivation and 

 preparation adopted under the varying condi- 

 tions of the great cacao-growing countries. 

 Throughout the book the usual E!nglish render- 

 ing, "cocoa," is adopted in preference to 

 "cacao." 



Among the most valuable chapters are those 

 dealing with the botanical characteristics of the 

 tree and its cultivation as a crop. The correct 

 understanding of the morphology and physiology 

 of the plant is of the greatest practical im|x>rt- 

 ance, and much of the author's convincing treat- 

 ment of the problems of cacao cultivation rests 

 upon his appreciation of this fact. Planters will 

 turn with interest to the discussion of the perennial 

 questions of " shade " and manures, while the 

 account of the progress made in Java with ex- 

 perimental grafting and budding of selected varie- 

 ties will be welcomed by West Indians, who were 

 the first to recognise the possibilities of this 

 practice. It would seem, however, that at present 

 Dr. van Hall does not fully share the optimism 

 expressed in certain circles in regard to the prac- 

 tical possibilities of this line of work. The author 

 will gain the confidence of planters and others by 

 his respect for the experience of sound, practical 

 men and avoidance of dogmatic assertion : " It is 

 a golden rule that cultural methods must always 

 be entirely dependent on local conditions." The 

 book is well printed and the numerous illustra- 

 tions are excellent. 



(2) Prof. Copeland 's well-illustrated book is 

 one of the best accounts of the science and practice 

 of coco-nut culture that has yet appeared. As 

 professor of plant physiology in the College of 

 Agriculture of the University of the Philippines, 

 the author has for some years past been occupied 

 with researches into the physiology of the coco- 

 nut palm, and the present volume is substantially 

 a discussion of the practical aspects of coco-nut 

 growing in the light of the results of his inves- 

 tigations. As main topics the author deals with 

 the physiology of the palm, climate and soil, 

 diseases, selection of seed,> field culture, and 

 coco-nut products. His own practical experience 

 has been the basis for his treatment of planting 

 practice, and, in consequence, the book is chiefly 

 concerned with coco-nut planting as carried out 

 in the Philippines. Special value attaches to the 

 chapters on climate, soil, and culture, since, as 

 might be expected, they have been written with 

 full regard to the physiology of the plant, a subject 

 dealt with all too briefly in an excellent and 



