38o 



NATURE 



{August 8, 1878 



alphabetical order of all the known American tribes and 

 their languages. Each volume has a good useful index, 

 a most important item in a work of this nature. 



The abundant equipment of maps adds greatly to the 

 value of the volumes, as the numerous illustrations do to 

 their interest. 



OUR BOOK SHELF 



Geometry in Modern Life, being the Substance of Two 

 Lectures on Useful Geometry, given before the Literary 

 Society at Eton. By J. Scott Russell, F.R.S. (Eton : 

 WiUiams and Son, 1878.) 



-In a recent number (Nature, vol. xviii. p. 263) we took 

 occasion to suggest that the usefulness of a school scien- 

 tific society might still further be increased by calling in 

 the assistance of scientific men to deliver lectures which 

 should be open not merely to the members, but also to a 

 v/ider circle. The literary Society at Eton has, webeliere, 

 adopted this plan on very many occasions ; recently it 

 will be remembered that Mr. Gladstone addressed the 

 society on Homer. Mr. Russell's lecture is a full one, 

 and on the lines which it follows, a useful one. " Geo- 

 metry is a pure science, gives logical training, is a disci- 

 pline of thought, is an instrument of human culture, 

 and has high educational value. But geometry is 

 equally the development of a method pervading nature ; 

 its mastery gives man a power to govern matter. 

 The training which enables him to comprehend the 

 mechanism of the universe, enables him also to make 

 creations 'of his own in harmony with those greater 

 designs of which his OAvn are but a small portion. 

 These two uses of geometric education the one purely 

 gymnastic, the other practical and technic, may be so 

 combined that each shall aid and not impede the other. 

 The order, number, and measure which pervade the 

 universe can be easily brought within the scope of ele- 

 mentary education, and so form the fit preparation for 

 scientific observation and experiment in later life, by 

 means of which the standard of application of abstract 

 truths to matter and events in human life are determined 

 and made familiar. But the one learning cannot be too 

 soon begun, nor the other too long continued, and each is a 

 material aid to the other." This extract shows the 

 author's views, which he has worked out in some detail. 

 Starting from the Greek geometry, he passes on to useful 

 geometry : its applications to land-measuring, trigo- 

 nometry, navigation. He touches also on numbers, 

 goes on to symmetry, harmony, melody, then to light, 

 shape, and shadow. He closes with a chapter on matter, 

 force, and motion. To sum up, the whole furnishes a 

 quantity of illustration from an eminent practical man, 

 which is likely to be profitable to teachers in search of 

 such illustration — to allure the "what's the use of it?" 

 boys who form a part of every mathematical master's 

 geometrical classes. 



Die Geologic der Gegejiwart. Dargestellt und beleuchtet 

 von Bernhard von Cotta. Fiinfte umgearbeitete 

 Auflage. (Leipzic: J. J. Weber, 1878.) 

 The appearance of a fifth edition of von Cotta' swell- 

 known Avork is a sufficient proof of its popularity — a 

 popularity which, in spite of some unfortunate drawbacks 

 to its usefulness, we cannot but regard as being well 

 deserved. Since the first appearance of the volume in 

 1866 it has been steadily growing in bulk, and in the 

 present edition the author has brought his work up to 

 date by noticing the principal contributions which have 

 recently been made to geological science. Among such 

 additions we may point to his notices of the method of 

 study of rocks by the means of the microscope, of the 

 new classification and nomenclature of the stratified 

 rocks suggested by Carl Mayer, of the results of the 



Challenger expedition, of the latest speculations on the 

 causes of volcanic activity and the nature of meteorites, 

 and of CroU's theory of the recurrence of glacial periods. 

 The coloured frontispiece now added to the work, we can 

 scarcely regard as an improvement, seeing that it tends 

 to perpetuate those views of the restriction of certain 

 classes of volcanic products to distinct geological periods, 

 which, though so frequently insisted upon by German 

 petrographers, do not appear to be sustained by extended 

 observation in the field. 



Ocean and Her Rulers. By Alfred Ehves. New and 

 Revised Edition. (London : Griffith and Farran, 

 1878.) 



Under the Red Ensign. By Thomas Gray. (London : 

 Simpkin, Marshall, and Co., 1878). 



These are two good books, each in its way. The former 

 is a narrative of the nations which have from the earliest 

 ages had dominion over the sea, comprising a brief his- 

 tory of navigation down to the present time. It is evi- 

 dently intended for boys and is likely to interest the more 

 thoughtful of them and send them to works which will 

 give a nlore detailed account of the peoples whose ex- 

 ploits by sea are told, and lead them to take an interest 

 in geographical discovery. The reading is rather miscel- 

 laneous and unconnected, and the information sometimes 

 undigested, but as a whole the book is useful and 

 interesting. 



Mr. Gray's booklet is one that will prove thoroughly 

 useful to parents intending to send their boys to sea, as 

 well as to the boys themselves. Mr. Gray knows well 

 what he writes about, and the information and advice he 

 gives as to the choice of a sea-life as a calling, how to get 

 a boy launched into it, what kind of ship to choose, how 

 the boy should conduct himself, what books he should 

 read, and a multitude of other points are admirable. We 

 are glad to see that among the books he recommends a 

 large proportion are standard scientific works. 



Memoir of the late Alfred Smee, E.R.S., by his Daughter. 

 With a Selection from his Miscellaneous Writings. 

 (London : George Bell and Sons, 1878.) 

 Mr. Smee was in many respects a remarkable man, and 

 this readable memoir by his daughter will, we doubt not, 

 be acceptable to those who knew him personally or 

 through his works. An Appendix contains about forty 

 papers, letters, pamphlets, &c. ; these occupy quite two- 

 thirds of the volume. 



LETTERS TO THE EDITOR 



[ The Editor does not hold himself responsible for opinions expressed 

 by his correspondents. Neither can he undertake te return, 

 or to correspond -with the writers of, rejected manuscripts. 

 No notice is taken of anonymous communications. 



[The Editor urgently requests correspondents to keep their letters as 

 short as possible. The pressure on his space is so great that it 

 is impossible otherwise to ensure the appearance even of com- 

 munications containing^ interesting and novel facts.l 



An Intra-Mercurial Planet 

 With reference to the important announcement, by telegram, 

 of the discovery by Mr. Watson of an intra-Mercurial planet 

 during the late eclipse of the sun, it may be worth remarking 

 that the position of Q Cancri agrees very well with that given in 

 the telegram published in Nature, and that there may be a 

 possibility that the object observed is in reality this star. The 

 position of the suspected planet recorded by Mr. Watson is 

 R.A. 8h. 26m., and N.P.D. 72°; the apparent place of the 

 star, computed from the mean place given in the new Nine- 

 Year Catalogue for 1872, January I, is, for July 29, R.A. 8b. 

 24m. 40S., and N.P.D. 71° 29' 40". The magnitude of this star 

 is, however, smaller than that given by Mr. Watson, that in the 

 British Association Catalogue being s\, and that in Argelander's 



