3^-^ 



NATURE 



[June 28, 1917 



given to the numerical ones, and references to 

 the text in the case of the descriptive ones. We 

 have satisfactorily checked some of the calcula- 

 tions, and the book is laudably free from mis- 

 prints. There is little original matter in the 

 work, but the author shows good judgment and 

 no little knowledge in his selection and treatment 

 of the various branches of this important subject. 

 We are sorry that the author was compelled 

 by considerations of space to devote little more 

 than half a page to the important subject of light- 

 ning arresters. He divides them (p. 279) into (i) 

 the aluminium cell arrester, (2) the spark-gap 

 arrester, and (3) the non-arcing arrester. We 

 usually divide them into (ij the electrolytic, (2) 

 the intermittent, and (3) the continuous types of 

 arrester. Engineers are probably familiar with 

 the devices mentioned, but the non-technical 

 reader will have to look up the references given 

 at the bottom of the page. The numerous 

 references form a useful feature of the book. 



A. Russell. 



COTTON CULTIVATION IN THE UNITED 

 STATES. 



Field Crops for the Cotton-Belt. By Prof. J. O. 

 Morgan. Pp. xxvi + 456. (New York : The 

 Macmillan Co. ; London : Macmillan and Co. , 

 Ltd., 191 7.) Price js. 6d. net. 



"T^HE "Rural Text-book Series " has furnished 

 -'- the agricultural students of the United States 

 of America with several very useful volumes. Prof. 

 Oscar Morgan's contribution now before us 

 worthily upholds the reputation of the series, 

 and is likely to be accepted as having a value 

 considerably beyond the sphere of usefulness very 

 possibly contemplated for it by its author. 



Coming from an expert resident in Texas (the 

 most important of the cotton-producing ^tates), 

 the book will be appreciated by cotton-growers 

 throughout the world. In that light it is perhaps 

 unfortunate that so much elementary science was 

 thought necessary. The first principles of the 

 physiology and chemistry of plant life might have 

 been left to the lower school text-Book. A glos- 

 sary of terms would have got over any difficulty 

 presumed to exist and might, at the same time, 

 have been made useful to the general reader not 

 familiar with American agricultural terms and 

 expressions. For example, it is somewhat amus- 

 ing to' find the expression "Irish potato"; 

 tobacco a stimulant ; buckwheat a cereal ; the 

 "cotton square"; the "Corn-Belt"; the silking 

 of corn, etc. 



Setting these minor considerations on one side, 

 there are numerous features of the work of great 

 merit. It is a considered and practical exempli- 

 fication of the actual conditions and experience of 

 cotton production of the States, framed primarily 

 for use in schools and colleges. 



Limitations of space will not permit of a 

 detailed analysis, but it" may suffice if we indicate 

 one comparative aspect, namely, between the 



NO. 2487, VOL. 99] 



States and India, as illustrative of the numerous 

 practical bearings of the book. Prof. Morgan 

 describes very fully ten of the associated crops in 

 the Cotton-Belt. The first and most important 

 is corn, or, as in Europe it is more generally 

 called, Indian-corn (Zea Mays). This, it would 

 seem, occupies 38 per cent, of the belt,' while 

 cotton takes 39 per cent. ; then follow (but far 

 behind in point of area) oats, 3*7; wheat, 3*5 » 

 kafir and milo, i"4; pea-nut, 0*9; rice, o*8; 

 sugar-cane, o'6 ; while sweet sorghum, rye and 

 barley show still smaller percentages. Practi- 

 cally all the cotton, sugar-cane, rice and pea-nuts 

 grown in the United States come from the 

 Cotton-Belt. 



It may now be useful to exhibit a parallel 

 assortment of the crops associated with cotton in 

 India. Indian-corn, sugar-cane, rice, pea-nuts 

 are not recognised as important crops in, and the 

 Indian supplies of these are not drawn from, the 

 cotton-producing districts. Oats and rye (except 

 on the hills) can scarcely be said to be grown in 

 India. Barley and wheat only occasionally 

 accompany cotton, the former, as a rule, being 

 m.ainly produced outside the cotton districts. On 

 the other hand, Sorghum (jtiar), Pennisetum 

 (bajra), Cajanus (pigeon-pea), Sessapium {til 

 seed), Linum (linseed), and Hibiscus cannnhinus 

 (Deccan hemp) are very closely associated with 

 the Indian cotton. 



The Indian crops associated with cotton might 

 be described as a slightly more tropical set than 

 the American, and they denote at the same time 

 differences in soil, climate, seasons of growth, 

 tillage, manuring, and stock — differences that col- 

 lectively account very possibly for the lower grade 

 of the staple in India as compared with that of the 

 United States. And perhaps the most vital 

 aspect of these differences is the fact that the 

 Indian cotton associates can scarcely be spoken 

 of as rotated with it. 



The Indian rotation, such as it Is, is usually 

 within the year, not after the lapse of one or more 

 years. That is to say, two crops are taken off 

 the same field every twelve months, one being 

 cotton and the other the • alternate crop. Inter- 

 planting is also largely followed, more especially 

 with pigeon-pea (Cajanus), or with juar 

 (sorghum, but only rarely the sweet sorghum), 

 the balance in the soil being - thereby to some 

 extent preserved. Thus, while in India cotton 

 is often grown year after year on the same field, 

 our author tells us that in the States a three- or 

 four-year rotation is universally accepted as 

 essential. Thus: i, cotton; 2, corn; 3, oats and 

 wheat ; and 4, cow-peas. 



A study of the lx)ok leaves the conviction of its 

 practical utility so deeply impressed that one is 

 constrained to recommend improvement of exist- 

 ing supplies (especially Indian) on the lines set 

 forth by our author as a more rational procedure 

 than the discovery of new. areas of production. 



The book may be commended to all persons 

 interested in cotton or the associated crops of 

 cotton. 



