November 2, 19 11] 



NATURE 



in the botanical exploration of the Kentani district, 

 and to whom are dedicated the two new species of 

 Mystacidium figured — her own discoveries. To these 

 and others Dr. Bolus gives grateful recognition in his 

 introductory note. 



An index comprising a Hst of species and synonyms 

 is placed at the end of the text matter, and a good 

 portrait of the author as a frontispiece is a pleasing 

 addition. A, B. R. 



THE STUDY OF FIELD CROPS. 

 Southern Field Crops (exclusive of Forage Plants). By 

 Prof. J. F. Duggar. Pp xxvii + 579. Rural Text- 

 book Series ; edited by L. H. Bailey. (New York : 

 The Macmillan Co. ; London : Macmillan and Co., 

 Ltd., 191 1.) Price ys. 6d. net, 



AT a certain stage in his studies the agricultural 

 student is called upon to consider crop-growing 

 in its economic aspects, and he soon finds himself in 

 a wide and rather indefinite field, where, in theory, his 

 chemistry, botany, entomology, &c., ought to meet, 

 and where the bearing of all the sciences on practical 

 agriculture ought to be made manifest. In theory the 

 student is to be directed in his studies of this branch 

 of the subject by a man whose attainments in these 

 several sciences is beyond reproach, and who has also 

 a first-hand acquaintance with the economic problems 

 involved. But in practice this ideal combination is 

 never attained, and consequently the study of field 

 crops goes in with agriculture, and is left entirely to 

 the empiricist, no man of science having set up any 

 claim to deal with them from the economic point of 

 view. 



Like other teachers of agriculture, Mr. Duggar is 

 an empiricist ; but he is an enlightened one, and makes 

 liberal use of the data accumulated by his confreres 

 on the science side. He deals, as one would expect, 

 Vei-y fully with maize and cotton, to each of which 

 some ten chapters are devoted, the rest of the book 

 being occupied with the less common crops — wheat, 

 oats, sorghum, rice, &c. The usual arrangement of 

 the subject-matter is to begin with the structure of the 

 plant; then to pass on to its races and varieties, the 

 methods of breeding or improvement, the soils and 

 fertilisers best adapted, the appropriate tillage and 

 cultivation, and finally the insect and fungoid pests. 

 Thus the whole field of science is covered, from 

 chemistry and botany to entomology. 



Considering how much such a task is beyond the 

 powers of any one man, Mr. Duggar has done remark- 

 ably well. The purist in method, of course, might 

 object to the empirical treatment of the subject, and 

 feel dissatisfied with the numerous bald statements, 

 such as " Insect pests [of oats] are the same as those 

 of wheat, except that the oat is not attacked by the 

 Hessian fly," just as the purist in language (and many 

 others as well) might object to another statement — 

 "ensilage is the verb, as ' to ensilage corn,' with the 

 accent on the middle syllable." But these difficulties 

 are inherent in the subject, and it would be unreason- 

 able to judge the book from a point of view other than 

 that from which it was written and will probably be 

 used. 



NO. 2IQ2. VOL. 881 



For in the meantime, while he is waiting for the 

 true scientific treatment of crop husbandry to be de- 

 veloped, the student needs some one book in which he • 

 can find collected all the information he wants about 

 ordinary crops. He is more concerned with the facts 

 themselves than with their bearing on one another or 

 on any central hypothesis. From this point of view 

 Mr. Duggar's book is very good ; there has obviously 

 been a great deal of work expended in collecting the 

 facts, and the references to the literature at the end 

 of each chapter, if not entirely satisfying to the man 

 of science, will at any rate put the student in touch 

 with other work on the subject. In the present state 

 of our knowledge the collection of the facts relating 

 to the growth of crops is extremely necessary for 

 further progress, and Mr. Duggar has contributed 

 material that will be found distinctly useful. 



As in the other members of this series, the book is 

 well illustrated, and the pictures are well chosen, there 

 being remarkably few of the ordinary useless field 

 views. "An honest book," Dr. Bailey calls it in his 

 introduction ; " . . . these makers of observation text- 

 books, that present the crops and the animals in their 

 real and living details, will set going a great quiet 

 movement to examine minutely the conditi9ns of agri- 

 cultural failure and success." E. J. Russell. 



PROPERTIES OF MATTER. 

 General Physics for Students : a Text-book on the 

 Fundamental Properties of Matter. By E. Edser. 

 Pp. ix + 632. (London : Macmillan and Co., Ltd., 

 191 1.) Price 75. 6d. 



IT is not often that a text-book, published under 

 a familar title, presents so many novel and 

 valuable features as Mr. Edser 's latest production, 

 "General Physics for Students." It is scarcely too 

 much to say that with regard to contents and general 

 mode of treatment the book forms a class for itself. 

 By the collection of so much fresh material into one 

 volume, Mr. Edser has made accessible to students 

 many parts of physics, which, either from lack of 

 time or initiative, they have hitherto been unable to 

 appreciate. This has been done in no meagre fashion, 

 the details, both experimental and theoretical, being 

 consistently of a very comprehensive character. 



The very care which has obviously been bestowed 

 upon the work in order to suit it to the needs of 

 students has, we think, been the cause of the one 

 unfortunate feature of the book. This is the avoid- 

 ance of the use of calculus notation — a procedure 

 which the author seeks to justify in the preface. 

 There is undoubtedly much to be said for such omis- 

 sion in the case of . junior students whose teaching 

 involves but rare recourse to calculus methods; but 

 to continue the practice through a book of this kind is 

 open to grave objections. The students who use the 

 book may be divided into two classes — those sufficiently 

 acquainted with calculus notation and methods, and 

 those ignorant of them. The former class are liable 

 to become annoyed at the repeated integration from 

 first principles of the same function ; the latter class 

 may become accustomed to regard the laborious pro- 

 cesses given as essential parts of the problems in 



