240 



NATURE 



[May 18, 1916 



Electrical Apparatus-making for Beginners. By 

 A. V. Ballhatchet. Pp. 164. (London : P. 

 Marshall and Co., n.d.) Price 25. net. 

 The author has provided, at a moderate price, 

 a very useful little book, which should do much 

 to encourage the beginner to construct simple 

 electrical apparatus with which to make a number 

 of instructive experiments. The book is illus- 

 trated with a number of photographs of the 

 apparatus described, which the author has himself 

 constructed. In addition, there are good work- 

 ing drawings and diagrams of connections where 

 these are helpful. The real utility and educa- 

 tional value of work of this kind to the beginner 

 cannot be insisted upon too often. He has read 

 of and perhaps seen professionally made appa- 

 ratus, and he naturally supposes that nothing 

 within his constructive power can be any good, 

 and more especially is this the case if he is not 

 already fairly accomplished in the use of tools. 

 While his earlier efforts may not be much use to 

 anybody else they are of immense value to him — 

 that is, if he has any perseverance. He may 

 gradually come to learn that rough-looking appa- 

 ratus may really work up to a point well, and so 

 begin to acquire that confidence in himself which 

 is essential when, at a later stage, he has original 

 ideas. He may then either make preliminary 

 rough experiments to see if, with better work, 

 they promise to succeed, or if he has become a 

 good manipulator he may have discovered that he 

 can carry out his own ideas quickly and with 

 sufficiently good work in the essential parts to 

 get better results than he could hope for if he 

 depended entirely upon others to put his ideas 

 into form. ' C. V. B. 



Guida alio Studio della Storia delle Matematiche. 

 By Prof. Gino Loria. Pp. xvi + 228. (Milano : 

 Ulrico Hoepli, 1916.) Lire 3. 



The plan of this work is rather unusual, but quite 

 good. The first part gives, among other things, 

 references to first-rate works on history and his- 

 torical method in general {e.g. Bernheim, Lavisse 

 et Rambaud, Merz), besides works on the history 

 of mathematics in particular. We also find here 

 summaries of , the contents of the more important 

 journals dealing with mathematical history. The 

 second part is more specialised ; there are sections 

 on manuscripts, biographies, editions of collected 

 works, mathematical correspondence, biblio- 

 graphy, catalogues, and so on. There is a name- 

 index for each part separately. The amount of 

 information given is really remarkable, and It is 

 well up to date; the author, too, has not shrunk 

 from the disagreeable duty of pointing out works 

 (such as those of Montucla, and even of M. 

 Cantor) which must be used with caution. 



There are a good many misprints, especially in 

 English names and words (Raleigh, for instance, 

 passim) ; we even find our familiar friend Bernouilli 

 (p. 166); but few, if any, are serious, and the 

 wonder is that they are not more numerous than 

 they are. 



G. B. M. 



NO. 2429, VOL. 97] 



LETTERS TO THE EDITOR. 



[The Editor does not hold himself responsible for 

 opinions expressed by his correspondents. Neither 

 can he undertake to return, or to correspond with 

 the writers of, rejected manuscripts intended for 

 this or any other part of Nature. No notice is 

 taken of anonymous communications.] 



A Suggestion with regard to Genera Splitting. 



Individual systematic botanists and zoologists differ 

 much in the principles which guide them with regard 

 to the "splitting," or "lumping," of genera. Much 

 can be said on both sides. The splitting into smaller 

 genera of a genus overloaded with species should help 

 to show the more intimate relationships of the species 

 to each other. On the other hand, if the new ^enera 

 have names unlike the original genus, the kinship of 

 all the species originally included in the one genus 

 is, to the casual observer, more or less masked. When 

 a genus is very small in species a better grasp of thei;- 

 relationship with each other is probably gained by 

 retaining them all under one generic name, even 

 though morphological characters may well warrant 

 placing each species in a distinct genus. In botany 

 in Australia several hundred species are included in 

 the genera Eucalyptus and Acacia. Unquestionably a 

 better grasp of the kinship of the individual species is 

 obtained by leaving all in the two genera named rather 

 than in instituting new genera for various groups, but 

 it is equally certain that some day a " splitting " 

 systematist will erect new genera, which will not, I 

 believe, help us in "memorising" the groups as 

 wholes. 



Some time ago, in discussing this question with my 

 friend, Mr. G. M. Matthews, whose valuable work on 

 the "Birds of Australia" is now in the press, I sug- 

 gested that the letters of the Greek alphabet should be 

 used, when genera splitting is decided on, as a prefix 

 to the original generic name, thereby showing the 

 common relationship of all the species to each other. 

 May I make this suggestion here in your columns, and 

 add, further, that the relationship would be still more 

 clearly shown if the Greek symbol were used rather 

 than a " translation " into English? The original genus 

 (i.e. the " split " part, containing the original type 

 species) would be best represented as a, though diffi- 

 culty would arise in thus altering the original generic 

 name; so, unless zoologists and botanists could come 

 to some international agreement on the matter, it 

 would probably be necessary to use no prefix in this 

 portion of the "split," but add (S.S.—sensu stncto) to 

 the simple generic name. The "splits" could then be 

 fi, 7, etc. To take the genus Eucalyptus, for example, 

 we should have a-Eucalyptus, or Eucalyptus (5.5.), 

 ^-Eucalyptus, y-Eucalyptus, etc. Such a method of 

 splitting would be convenient and handy, would still 

 show the broader relationships of the species, and 

 would not interfere with those systematists who dis- 

 approve of splitting, since these need only drop the 

 prefix. J. Burton Cleland. 



Department of Public Health, 

 Sydney, Australia. 



The Place of Science in Education. 



The question as to whether modern education should 

 be classical and literary, or' scientific, is one which 

 apparently, in certain high quarters, is still con- 

 troverted. This matter, once said. John Stuart Mill, 

 is very rnuch like a dispute "whether a tailor should 

 make coats or trousers." Replying in the philo- 

 sopher's own words, "Why not both? Can anything 

 deserve the name of a good education which does not 

 include literature and sciencetoo? If there were no 



