January ii, 19 12] 



NATURE 



;6i 



UkYER'S PAPERS ON THE CONSERVATION 

 OF ENERGY. 



T^HE recent issue as one of the volumes of Ostwald's 

 " Klassiker der exakten Wissenschaften " of Robert 

 Mayer's two papers of 1842 and 1845, on the subject now 

 known as the conservation of energy, will prove a great 

 boon to those interested in the early history of that great 

 generalisation. Traces of the idea may be found amongst 

 the ancients, and Descartes held that it was a self-evident 

 truth. But in the middle of the seventeenth century the 

 term energy had but a vague significance, even in the 

 simple case of a moving body, and the doctrine of con- 

 servation, when held, meant little or nothing for physical 

 science. Towards the middle of the nineteenth century 

 interest in the question appears to have been widespread. 

 S^guin in France in 1839 calculated the mechanical 

 equivalent of heat from the fall of temperature of 

 steam when expanding against external pressure ; Joule 

 in England in 1840 showed that when a battery of 

 cells drives a motor the consumption of zinc in the cells 

 is proportional to the work done by the motor ; and Mayer 

 in Germany, after explaining how the term energy was to 

 be understood, stated the generality of the law in his 

 first paper in 1842, and with greater clearness in his 

 pamphlet of 1845. 



The titles of Mayer's publications were not such as 

 to suggest the subjects treated in them, and they were 

 so little known, even in Germany, that Helmholtz in 

 1847 published his paper on the subject without any refer- 

 ence to Mayer. In the meantime, Colding in Den- 

 mark had read a paper to the Royal Society of Copen- 

 hagen in 1843 in which he stated clearly the law of con- 

 servation of energy, and Joule read before the British 

 Association in the same year the first of his papers on the 

 measurement of the mechanical equivalent of heat. Before 

 the middle of the century Joule's experimental work had 

 placed thermodynamics on a firm basis. When the contri- 

 butions of S^guin and of Colding, and possibly of others 

 whose work has been overlooked, are republished in a 

 form as accessible as are those of Mayer, Joule, and Helm- 

 holtz, it may be possible to apportion' the credit for one of 

 the greatest generalisations of the nineteenth century in a 

 way to satisfy even the most captious critic. 



NATURAL SELECTION IN MAN. 

 TV/TR. E. C. SNOW, in his paper entitled "The Intensity 



of Natural Selection in Man " (Drapers' Company 

 Research Memoirs, Studies in National Deterioration, 

 No. vii. London : Dulau and Co., 191 1), has set himself 

 to answer the following question : Has heavy infantile 

 mortality any selective value or tendency to eliminate the 

 more sickly and to spare the hardier children? Of the 

 data available for the investigation of this problem, the 

 most satisfactory are derived from the annual volumes of 

 Prussian statistics, and the most definite of the results 

 were obtained from them. In order to indicate the method 

 employed, one example will be described. Thirty rural 

 districts in Prussia were taken, and all the children in 

 them born in the year'1881 were considered. It was ascer- 

 tained for each district how many of these children died in 

 the first two years of life and how many in the next eight. 

 Now it is obvious that if the infantile mortality tends 

 to weed out the weaker children, then in those districts 

 in which the mortality among the children born in 1881 

 was highest in the years 1881 and 1882 it should tend to 

 be lowest in the years 1883-90, since stronger children less 

 hkely to succumb to the ailments of childhood would have 

 survived their first two years. In other words, there will 

 be a negative correlation between the number of deaths in 

 the first two years of life and the number in the next 

 eight, provided that allowance is made for the total number 

 of births in each district for the year i88i and for the 

 eflects of environment. After making these necessary 

 allowances by means of the formula for partial correlation, 

 a coefficient of -093 was obtained in the case of males 

 and of -085 in the case of females. 



These results, considered by themselves, would seem to 

 show that the selective action of infantile mortality was 

 very strongly marked; but it is perhaps unnecessary 'to say 



NO. 2202, VOL. 88] 



that the author, whose work bears every sign of the most 

 painstaking care and thoroughness, has brought forward a 

 considerable body of additional evidence derived from data 

 of a similar nature collected both in England and Germany. 

 The greater part of it corroborates the conclusion stated 

 above, though the correlation coefficients were in no other 

 cases found to be so high, and in some cases the sign was 

 actually positive. Yet we are of opinion that, on the 

 whole, the author is justified in saying : " Natural selec- 

 tion in the form of a selective death-rate is strongly 

 operative in man in the earlier years of life." A word of 

 praise must be added on the composition of the memoir : 

 it is fair, clear, and interesting. 



E. H. J. S. 



THE KING ON EDUCATION IN INDIA. 



TOURING his visit to Calcutta the King-Emperor and 

 Queen-Empress received in the Throne Room an 

 address from the University of Calcutta. The address was 

 read by the Vice-Chancellor of the University, Sir Asutosh 

 Mukharji, and Lord Hardinge, the Governor-General, was 

 present in his capacity of Chancellor of the University. In 

 his reply to the address the King-Emperor said : — 



" I recall with pleasure the occasion on which, six years 

 ago, I received from the University of Calcutta the 

 honorary degree of a Doctor of Law, and I am glad to 

 have an opportunity to-day of showing my deep and earnest 

 interest in the higher education of India. It is to the 

 universities of India that I look to assist in that gradual 

 union and fusion of the culture and aspiration of Europeans 

 and Indians on which the future well-being of India so 

 greatl)' depends. I have watched with sympathy the 

 measures that from time to time have been taken by the 

 universities of India to extend the scope and raise the 

 standards of instruction. Much remains to be done. No 

 university is nowadays complete unless it is equipped with 

 teaching faculties in all the more important branches of 

 the sciences and the arts, and unless it provides ample 

 opportunities for research. You have to conserve the 

 ancient learning and simultaneously to push forward 

 Western science. You have also to build up character, 

 without which learning is of little value. You say that 

 30U recognise your great responsibilities. I bid you God- 

 speed in the work that is before you. Let your ideals be 

 high and your efforts to pursue them unceasing, and, under 

 Providence, you will succeed. 



" Six years ago I sent from England to India a message 

 of sympathy. To-day in India I give to India the watch- 

 word of hope. On every side I trace the signs and 

 stirrings of new life Education has given you hope ; and 

 through better and higher education you will build up 

 higher and better hopes. The announcement was made ai 

 Delhi by my command that my Governor-General in 

 Council will allot large sums for the expansion and 

 improvement of education in India. It is my wish that 

 there may be spread over the land a network of schools 

 and colleges, from which will go forth loyal and mani\ 

 and useful citizens, able to hold their own in industries 

 and agriculture and all the vocations in life. And it is 

 my wish, too, that the homes of my Indian subjects may 

 be brightened and their labour sweetened by the spread of 

 knowledge with all that follows in its train, a higher level 

 of thought, of comfort, and of health. It is through educa- 

 tion that my wish will be fulfilled, and th(> cause of 

 education in India will evei" be very close to my heart. 



"It is gratifying to me to be assured of your devotion 

 to myself and to my house, of your desire to strengthen 

 the bonds of union between Great Britain and Indi.i, and 

 of your appreciation of the advantages which you enjoy 

 under British rule. I thank you for your loyal and dutiful 

 address." 



Since the now University Act was passed in 1904, con- 

 siderable and satisfactory progress has been made in India 

 in all branches of education, and the university standards, 

 in particular, have been raised and made more real and 

 effective. There are many signs of educational activity in 

 India, and if the true purpose of education be kept well 

 in mind the country will enter upon an era of iiureascd 

 prosperity based upon increase of knowledge. 



