6o4 



NA TURE 



[April 30, 1896 



OUR BOOK SHELF. 

 Grtindriss der Psychologic. By Wilhelm Wundt. Pp. 



xvi + 392. (Leipzig: Wm. Engelman.n, 1896.) 

 This is the third book on psychology which Prof. Wundt 

 has written, and its special aim is to give an account of 

 the general principles of the science apart from phy- 

 siological considerations on the one hand, and philoso- 

 phical on the other. Technical details are to a large 

 extent omitted, the reader being referred for them to the 

 "Grundziige der physiologischen Psychologie." The 

 book resembles in many respects Kiilpe's " Outlines," 

 and it seems as if the author intended it to correct the 

 departures from the Wundtian standpoint which are to 

 be found in the latter. A novel feature of the book is the 

 description of ideas, emotions and volitions as psychical 

 structures ("Gebilde"), with the reservation, however, that 

 both the structure and the elements of which they are com- 

 posed are to be regarded as processes and not as objects. 

 After considering psychical elements and " Gebilde," the 

 subjects of consciousness and attention, association and 

 apperception take up a third section ; the fourth section 

 treats of mental development in the animal and the child, 

 and the book concludes with the formulation of certain 

 laws of psychical causality. 



Cours de Physique, de PEcole Polytechnique. By M. J. 



Jamin. Premier Supplement. By M. Bouty. Pp. 



182. (Paris: Gauthier-Villars et Fils, 1896.) 

 This supplement to the latest edition of the " Cours de 

 Physique " of Jamin and Bouty, deals with progress in 

 heat, acoustics, and optics. It is not intended to be a 

 complete account of work done in these three sections of 

 physical science, but a description of investigations which 

 have led to definite results likely to survive for some 

 years. In the section on heat, the work described is 

 concerned with the measurement of temperature, prin- 

 ciples of thermodynamics, changes of state, dissociation, 

 osmotic pressure, critical points, and capillary pheno- 

 mena. In the section on acoustics and optics, the 

 subjects of the chapters are : propagation of vibratory 

 movements, propagation of sound, study of vibrations, 

 propagation of light, and diffraction, interference pheno- 

 mena and their applications. Students of physics will 

 find the volume useful for consultation, especially as 

 references are always given to the papers abstracted. 



Les Rayons X, et la Photographic a travers les Corps 

 Opaques. By Dr. C. E. Guillaume. Pp. viii + 127. 

 (Paris: Gauthier-Villars et Fils, 1896.) 



This is the fullest and most scientific account we have 

 seen of work with X-rays, and the investigations which 

 led up to Rontgen's discovery. The first part of the 

 book contains a general account of the kinetic theory of 

 gases and the nature of light, together with a few par- 

 ticulars with reference to electric discharges in gases. 

 These facts, and the statement of the theories upon 

 which they depend, prepare the way for a concise 

 description of researches on the luminous phenomena 

 exhibited by electric discharges in rarefied gases, from 

 the times of Faraday and Hittorf until now, especial 

 attention being given to the bearings of these investiga- 

 tions upon the nature of kathode rays. Rontgen's dis- 

 covery, and many of the researches to which it has given 

 rise, together with an account of its applications, make 

 up the remainder of the volume. Most of the results 

 described have appeared in the Comptes rcndus of 

 the Paris Academy of Science, or in Nature, and Dr. 

 Guillaume has now brought them together in a handy 

 form. Having regard to the large amount of work still 

 in progress, the volume can hardly be considered as per- 

 manent in its present shape ; but when the proper time 

 arrives, it may be expanded, and will then make a 

 handbook well worth a place in scientific libraries. 



NO. 1383, VOL. 53] 



LETTERS TO THE EDITOR. 

 [2Vie Editor does not hold himself responsible for opinions ex- 

 pressed by his correspondents. Neither can he undertake 

 to return, or to correspond tvith the writers of, rejected 

 manuscripts intended for this or any other part of Nature, 

 No notice is taken of anonymous cominunications.'\ 



Blood-Brotherhood. 



This very ancient custom, performed in so many ways, and 

 still practised by all barbarous and semi-barbarous peoples, 

 might, by the help of modern science, be turned to useful and 

 beneficent ends. For some time I have thought, and the con- 

 viction grows on me, that residents and travellers in tropical 

 parts of the world might ihe better withstand the climate, 

 malaria and fevers to which they often succumb, by entering 

 into blood-brotherhood with a healthy native. 



The classical researches of Pasteur and his disciples have 

 shown how various diseases may be controlled, and immunity 

 secured to man and the lower animals, by the proper use of anti- 

 toxins, and by diluted subcutaneous injections of virus in certain 

 cases of blood-poisoning. Although not parallel in specific aim, 

 blood-brotherhood may be found to possess similar prophylactic 

 properties. Is it not probable that a European inoculated with 

 the blood or serum of a native, would be better able to resist the 

 climatic changes to which he is subjected in tropical countries? 

 In other words, would blood-inoculation not set up in his system 

 those changes necessary to adapt him to the climate, and render 

 him immune to the diseases which are the result of climate? 

 The suggestion is based on the assumption that the native is more 

 healthy in his own climate than any foreigner can be, and that 

 blood-inoculation would acclimatise the latter at once. 



The advantages to be derived from such a system are obvious. 

 Only strong, healthy persons can long withstand the climate of 

 Central Africa. Many missionaries and pioneers are annually 

 sacrificed to it. Men certified by medical practitioners as sound 

 in lung and limb at home, are weakened and prostrated there. 

 A recent example of great loss of life due to climate was that of 

 the French expedition to Madagascar, where the army was 

 decimated from this cause. And another noted example is that 

 of the late lamented Prince Henry of Battenberg, who died on 

 his way to Ashantee of a disease brought on by climatic change. 

 I have referred to the writings of African travellers for 

 information on the effect on the system of blood-brotherhood, 

 without positive result. No one seems to have suffered by it. 

 Livingstone, Grant and Cameron mention the custom, and all 

 of them entered into it in the person of one of their attendants. 

 Perhaps they feared the consequences on themselves, but no 

 explanation is given. Stanley is the only traveller whom I have 

 been able to find entered into blood-brotherhood in person. At 

 first he, too, seems to have done so by proxy, but afterwards he 

 took part in it fearlessly, and underwent the operation fifty 

 times! So that Trumbull (" The Blood Covenant," p. 38) is 

 justified in saying that " the blood of a fair proportion of all the 

 first families of Equatorial Africa now courses in Stanley's 

 veins." We have not been told that Stanley suffered in any 

 way from these inoculations. We may therefore conclude with 

 a fair degree of reason that his healthiness (on the whole), 

 endurance and success, was attributable in some measure to the 

 exchange of blood with the natives he met. 



Blood-brotherhood as practised in Central Africa varies in 

 detail, and is accompanied by many formalities ; but the essential 

 part of the process, as described by Cameron ("Across Africa," 

 p. 333 ) consists in ' ' making an incision on each of the right wrists, 

 just sufficient to draw blood, a little of which is scraped off and 

 smeared on the others cut." In many cases the blood wasted 

 is considerable, but the science of to-day does not demand this. 

 It would only be necessary to use a small quantity, perhaps not '\ 

 more than the quantity of lymph required in small-pox inocula- ■ 

 tion. And it would be easy to get healthy natives at the port ; 

 of debarkation, willing, for a small remuneration, to supply the ; 

 necessary blood or serum. The operation might prove . 

 invaluable to persons joining the Civil or other Service in India 

 or the colonies, to missionaries appointed to tropical countries — 

 and, in fact, to all persons requiring to travel or reside in hot or 

 unhealthy climates. It might also be found of value were the 

 circumstances reversed — ^that is to say, with the natives of hot 

 climates coming to reside in this country, or with persons 

 electing to reside at home after long residence abroad. 



Experiments conducted in the direction I have indicated, 

 would, I believe, result in the acquisition of much useful and 



