Feb. 24, 1887] 



NA TURE 



3^9 



following years, under extraordinary diflficulties — political, 

 social, and geographical — determined the measure <if the 

 arc of the meridian from Dunkirk to Barcelona ; from 

 the ! 1 0,000,000th part of which arc the measure of the 

 metre was then derived. 



The author in stirring language recounts the dangers 

 and disappointments of the scientific men engaged in 

 this work during the Revolution — M&hain, Delambre, 

 Berthemie, Biot, Arago, Lenoir, and Lavoisier. He en- 

 deavours to awaken a warm and genuine admiration for 

 their labours, and to show that the love of science is in 

 some way natural to France. In pathetic words he re- 

 counts the dangers in the field : Mifchain's work in Spain, 

 his troubles at home, his recall, and return to Spain ; his 

 fears that the great measurement might never be accom- 

 plished ; and at last the sad end — M^chain's death in 

 1807 at Plana, a victim to yellow fever. Then follows the 

 appointment of Biot and Arago, and the account of their 

 doubts and difficulties in completing the measurements, 

 of the capture and imprisonment of Arago and Berthemie, 

 of their detention in Algiers, and of their ultimate ransom 

 and release. 



M. de Fonvielle traces the development of the new 

 system of weights and measures from the proposal of 

 Buffon in 1790 to take as a unit the length of the seconds 

 pendulum, to the report of the completion of the measure- 

 ment of the metre in 1809. He refers to the invitation 

 given by France in 1790 to our country, to join in an 

 international effort to adopt one weight and one measure 

 for all nations. This invitation, as experience has shown, 

 ought not to have been declined, but even now, owing to 

 the reluctance of English-speaking nations to abandon 

 their traditional units, a similar proposal might possibly 

 not be warmly received. 



M. de Fonvielle reminds his readers that the French 

 metric system must not be altogether regarded as a 

 French innovation, for the Chinese long ago adopted 

 a decimal system. It is to Shun, the sage, when Regent 

 of the Chinese Empire, B.C. 2287, that China owes its 

 decimal system, based on a so-called natural constant, 

 the length of the musical standard lii, or bamboo pitch- 

 pipe. 



Of course this little volume is intended for popular 

 reading, particularly in France. For the true account 

 of the circumstances and results of the measurement of 

 the arc of the meridian which passes through Paris, we 

 must go to the " Memoires" published by Mdchain and 

 Delambre in 1806, and to the observations of Biot and 

 Arago issued in 1821. 



OUR BOOK SHELF 

 Histoire Generate des Races Humaiiies. Introduction a 

 r Etude dcs Races Humaines — Questions Generates. 

 Par A. de Quatrefages, Membre de I'lnstitut. (Paris : 

 A. Hennuyer, 1887.) 



Prof, de Ou.\tref.\ge.s and M. E. T. Hamy propose to 

 edit a general history of the human race, and the present 

 volume, by Prof de Quatrefages, is intended for an intro- 

 duction to a series of monographs by various authors. 

 The dark races will be described by M. E. T. Hamy ; 

 the yellow races by M. J. Montana ; and the red races 

 by M. I.ucien Biart. These volumes are in course of 

 publication, and the first volume of the series, on the 

 .Aztecs, by M. L. Bert, has already appeared. There will 



be a volume on the Mongols, by M. J. Deniker, and one on 

 the Foulahs, by Dr. Tautain. 



In the present volume the general questions of ethnology 

 are treated of, and the subject of the classification of the 

 human race is passed in review. With that charming 

 style which characterises the writings of this author, 

 and which has for long made him one of the most 

 popular writers on scientific subjects in France, he here 

 gives -A. precis of the chief works treating on ethnology, 

 and decides that the human race must not be placed in 

 the same category with the animal race, because it 

 exhibits the presence of two additional phenomena, those 

 of morality and religion. 



On the question of the unity of the human species, too 

 often one of mere words, the pros and cons are placed 

 before the reader in a tabular form. In the chapter on 

 the first appearance of man, the various transformistic 

 theories are passed in review, and the views of Darwin, 

 Huxley, \'ogt, and Haeckel are alluded to ; but the author 

 for himself believes that any certain knowledge on this 

 point is beyond our actual powers. In other chapters, 

 the antiquity and geographical origin of the race are 

 treated of, as well as the subject of the peopling of the 

 globe and the acclimatisation of the species. Primitive 

 man is regarded as of distinct ethnic types, and from 

 these the races took their rise. Lastly, the physical, the 

 intellectual, and the moral and religious characters of 

 the races are discussed in some detail. The work is 

 supplied with numerous and excellent illustrations ; it is 

 printed in clear type on royal octavo paper, and forms a 

 handsome volume of nearly 300 pages. 



Grundziige einer Theorie der Izosntischen Atmosphdren mil 

 Ber'ucksichtigung der irdischen A tmosphcire. Von Wil- 

 helm Schlemiiller. (Prague.) 



In this pamphlet the author introduces a modification 

 into the ordinarily accepted dynamical theory of gases by 

 assuming that the molecules of a gas at uniform tem- 

 perature are all affected with absolutely the same linear 

 velocity as regards magnitude, instead of the temperature 

 being dependent on the mean or average velocity. This 

 of course greatly simplifies the labour of deducing the 

 fundamental relations between pressure, density, tempera- 

 ture, and the potential of external forces ; and he claims to 

 beable todeducethe relation, which for the terrestrial atmo- 

 sphere gives Bessel's refractions to 9o'(j7V) zenith distance ; 

 agreeing with the formuU^ found by Bauernfeind in 1862- 

 64. We may remark that the convertible equations are 

 reproduced in some cases with almost wearisome frequency, 

 and that Joule is twice called Jonle. 



Manual of Physical Geography of Australia. By H. 



Beresford de la Poer Wall, M.A. (Melbourne : 



Robertson.) 

 Thi.S little manual is written for Australian schools, and 

 may be accepted as a fair and trustworthy account of the 

 physical geography of Australia. For an exhaustive- 

 treatment of the subject the material is still wanting for a 

 large section of the continent ; on others, again, there i^ 

 abundance of material, and of these Mr. Wall has made 

 creditable use. It is a pity the book should be burdened 

 with such terrible lists of names as those on pp. 9 and 10 : 

 the author would have done much better had he shown 

 the relations of the leading capes to the general relief of 

 the land. 



An Intermediate Physical and Descriptive Geography, 

 abridged from the Pliysical, Historical, and Descriptive 

 Geoi^raphy of the late Keith Johnston. (London : 

 Stanford, 1886.) 



The late Keith Johnston's larger geography is on the 



whole the best general text-book of the subject in English. 



The present abridgment for middle-classes in schools 



seems to us judiciously done. 



