June 22, 1905] 



NATURE 



I?' 



light, we are told, produces first stimulation and then 

 depression, neurasthenia and even loss of memory. To 

 protect us from these terrible ills we require a skin so 

 highly pigmented that the sun's rays cannot influence 

 our delicate nervous organisation. The want of a suf- 

 ficiency of pigment in the skin, Dr. Woodruff informs 

 us, has played an important part in the history of the 

 world. The decline and fall of the Roman Empire 

 and the decay of Greece were, in his opinion, due to 

 the fact that the military forces of these powers were 

 largely recruited from the northern blonde races. 

 These dominating blondes, bred under cloudy skies, 

 were reduced to impotence because their skins were 

 insufficiently pigmented to resist the baleful influence 

 of the bright sun of the Mediterranean. Light, and 

 not luxury, was responsible. It is not surprising 

 to learn that the conduct of the schoolboys of New 

 York is worse on a bright June day than on a cloudy 

 day in winter, but we should have thought that the 

 author's reminiscences of his own school days would 

 have suggested that there were other more probable 

 causes than the irritating effect of the chemical rays 

 of light upon the schoolboy's nervous system. 



It is difficult to criticise an author who, in consider- 

 ing the experimental work of Ferni, whose opinion 

 differs from his own, says, " it seems certain that he 

 has been misquoted, and that the fact is the reverse of 

 what he is alleged to have said." It is surely usual in 

 a scientific treatise to verify references, but here, as 

 elsewhere, Dr. Woodruff appears to have been rather 

 hurried. 



While admiring the author's industry and his 

 courage in advancing his contentions, we cannot but 

 consider many of his conclusions unwarranted. With 

 the remark that it is a pity that our slum babies cannot 

 undergo such " torture," we cannot forbear quoting 

 the following statement of Dr. Woodruff : — 



" We moderns of the intelligent classes alone vio- 

 late the mother's instinct to hide away in the dark with 

 her baby, and we ruthlessly thrust it out into the sun's 

 rays, actually strapping the poor little sufferers into 

 their carriages and torturing them with the direct rays 

 of the sun pouring down into their faces." 



OUR BOOK SHELF. 

 Handbuch der Heidckultur. By Dr. P. Graebner. 



Pp. viii + 296. (Leipzig: W. Engelmann, 1904.) 



Price gs. net. 

 The German word " heide," like the English 

 "heath," is applied to very different types of vege- 

 tation. In the narrowest acceptation it signifies a 

 district covered with dwarf shrubs where ling or 

 heather predominates, and such a formation is not 

 uncommonly associated with loose, sandy soil. But 

 in north Germany " heide " implies a wood, usually a 

 pine wood, and the same conception attaches to it in 

 other parts of Germany, as, for instance, the Dres- 

 dener Heide. Heath is therefore not a formation 

 according to the ecological use of the word, but is 

 applied to land where certain physical conditions 

 prevail, and covers not only stretches of open wood- 

 land, but also grass and other moors, and may even 

 be extended to peats and bogs. One feature common 

 to these different formations is the presence of humus, 

 and this is included in the definition given by 

 Ramann. 



The suggestive views as to the formation of heaths 



NO. i860, VOL. 72] 



advanced by Dr. Graebner in 1901 have become 

 widely known, and have received very general accept- 

 ance. Heaths or moors may develop on sands or 

 under water, but in north Germany, at any rate, and 

 not improbably in other countries, much of the heath- 

 land has taken the place of forests. Opinions differ 

 as to the causes which have brought about the change. 

 Borggreve and Krause have attributed the disappear- 

 ance of forests to destruction by animals, but Graebner 

 attaches more importance to continual draining of 

 salts into the lower layers by percolating water. 

 .'\nother factor, which has not been sufficiently empha- 

 sised by Graebner, is the action of those bacteria 

 which give rise to humus in the absence of air. Want 

 of air no less than impoverishment of the soil plays 

 its part. 



-Although the. book is written for the practical man. 

 Dr. Graebner has included a certain amount of purely 

 scientific matter where it has a bearing on economic 

 problems, but the chapter written by Mr. O. von 

 Bentheim is more especially concerned with practical 

 considerations. It is evident that profitable cultiva- 

 tion of heath land requires not only careful and scien- 

 tific farming, but in some cases success can only be 

 attained by general cooperation of the farmers either 

 as a society or under Government supervision. The 

 preparation of the land for agricultural farming or for 

 tree planting is discussed in detail ; as a preliminary 

 deep ploughing is advisable and quite necessary where 

 moor-pan has formed. Moor-pan (Ortstein) is prac- 

 tically a layer of stone, which is formed when perco- 

 lating water containing humates reaches layers of 

 soil which are rich in mineral salts; the humates are 

 precipitated, and bind the particles of soil into a 

 stratum of stone, which as it thickens cannot be 

 penetrated even by tree roots. 



In the latter portion of the book the different 

 formations are considered from the purely botanical 

 standpoint according to the characteristic plants. The 

 problems connected with the cultivation of heaths are 

 complicated but interesting ; for this reason the 

 opinions of Dr. Graebner, who has made a careful 

 study of the subject, are the more valuable. 



/ Nuovi Indirizsi e le Promesse della Odierna Antro- 

 pologia. By Fabio Frassetto. Pp. 71. (Castello : 

 C. E. S. Lapi, 1905.) Price 3 lire. 

 This little work consists of a series of four lectures 

 which the author delivered as an introduction to his 

 course of anthropology in the 1904-5 session of the 

 University of Bologna, where, after a break of twenty 

 years, he has taken up the work begun by Sergi be- 

 fore his removal to Rome. .Appropriately enough, the 

 first lecture of the four deals with Sergi' and his prin- 

 ciples of skull classification, and sketches very briefly 

 the types and the deductions which Sergi draws from 

 them — Eurasian and Eurafrican forms, and five species 

 of pygmies — at the same time pointing out that many 

 of these • views are only provisional. Dr. Frassetto 

 holds that just criteria of race are of the utmost 

 importance, not only for the sociologist, which most 

 inquirers would be prepared to admit, but also for the 

 medical man, who will more readily diagnose the 

 maladies which he has to treat, in proportion as racial 

 morphology and pathology are determined with pre- 

 cision and at the same time it becomes possible to 

 classify the individual patient from an anthropological 

 point of view. If he is too sanguine in this, another 

 point on which Dr. Frassetto insists does not seem 

 beyond the range of practical politics ; this is the 

 development of pedagogic anthropology, which shall 

 regulate the education of the individual child by 

 scientific principles. Even here, however, at any rate 

 in our own case, the problem of feeding the child and 

 of providing it with a healthy body will probably 



