168 



NA TURE 



[Dec. 25, i884 



schools has been already noticed in Nature (vol. xxxi. 

 p. 19), and the paper before us, by the Principal of the 

 Royal Agricultural College, Cirencester, is another pro- 

 duct of the Conferences. The author looks on agriculture 

 broadly, as extending, like the theme of the poet of the 

 " Georgics," — 



"... super arvorum cultu per corumque 

 Et super arboribus," 



and in a well-reasoned and well-written paper pleads for 

 the teaching of the natural sciences, their facts, laws, 

 methods, and applications to agriculture, to those who 

 have the direction of agriculture in this country, or who 

 seek fortunes in the soils of new countries. Cowley, two 

 centuries ago, asked, " Who is there among our gentry 

 that does not entertain a dancing-master for his children 

 as soon as they can walk ? But did ever any father 

 provide a tutor for his son to instruct him betimes in the 

 nature and improvements of that land which he intended 

 to leave him ? " Though this reproach is not deserved 

 so much now as when it was written, it is still not wholly 

 unmerited, and will so remain until those who have the 

 possession and management of landed property shall re- 

 ceive some special training such as that sketched out by 

 Mr. McClellan. This training, if fairly common, would 

 do far more to mitigate agricultural depression than any 

 amount of piecemeal legislation. The paper is a useful 

 addendum to Mr. Jenkins's recent report on agricultural 

 education, and it may be commended to the attention of 

 landowners and others connected with agriculture. 



The Text of Euclid's Geometry. Book I., uniformly and 

 systematically arranged. With a discussion of Euclid's 

 application of logical principles, copious notes, exer- 

 cises, and a figure-book. By J. Dallin Paul, R.N. 

 (Cambridge : Deighton, Bell, and Co., 1884.) 

 This is a "prodigious" work of 182 pages demy 8vo, 

 printed on excellent paper, with clearly-drawn figures, 

 devoted to the " painful " elucidation of all the difficulties 

 to be found in the first book of Euclid's Geometry, with 

 such other matter as hath been adumbrated in the above- 

 cited title-page. The road may be an easy one to walk 

 in, all stones of offence being carefully put on one side or 

 so rearranged that the wayfarer may not stumble as he 

 saunters along it, but it certainly is a long road. The 

 tendency of modern agitation a few years ago was to con- 

 dense our text-books with a view to get up geometry in 

 the minimum of time, but experience has taught us that in 

 the majority of cases junior boys are very tender-footed, 

 and cannot be driven along the geometrical path, and so 

 there has been a reversion to the "grand old" book with 

 many an aid to lure the young into paths not naturally 

 attractive to them. We do not find fault with these 

 attempts — we have recently noticed in these columns two 

 admirable editions of the " Elements," — but Mr. Paul has 

 taken, we think, an extreme course : at some perhaps 

 not distant date, if this sort of editing is catching, we 

 shall have a similarly got-up work devoted to Euclid's 

 treatment of isosceles triangles with a preliminary chapter 

 on an axiom. 



Our author has had so much to do with Euclid that his 

 views of life have possibly got to be Euclid-tinted, and he 

 sees nothing but Euclid ! It would be no wonder, for his 

 own words are, in deprecation of the presumption of 

 adding another edition to the many that have gone before, 

 " having been teaching Euclid almost daily for the last 

 twenty years to pupils who, before coming under his 

 tuition, had learnt something of geometry from the dif- 

 ferent text-books in use during that time, he ventures to 

 think that this experience has made manifest to him the 

 principal advantages and disadvantages of these numerous 

 works, and thereby enabled him to present the proposi- 

 tions in the form most likely to be of educational value to 

 those who are beginning either to learn or to teach the 

 subject." We have allowed the author to put so much in 



evidence that the majority of our readers may gather that 

 this is not "just the book they wanted " for themselves, 

 and yet may see the scope of Mr. Paul's labours. 



We cannot commend the author's action in placing the 

 notes on the propositions in the early part of the book ; 

 experience has shown him that when placed in their usual 

 position at the end they are passed by, but their actual 

 position here offends our eye, and will not, we fancy, 

 secure the writer's object. We regret that the writer has 

 spent so much time and thought to so little purpose, as 

 we believe, for we cannot imagine who will be the public 

 that will purchase his book, its size and price are a bar to 

 its introduction into school use. We close with remark- 

 ing that there is a good deal that may be of use to (say) a 

 pupil-teacher, or to one who is not strong in geometry 

 and yet has to teach young pupils ; but much, if not all, 

 of this, can be got in handier text-books. A good feature 

 is the placing at the end the particular enunciations of 

 the propositions with the diagrams placed in positions 

 very different from those which they had in the text : this 

 would enable a pupil to test his acquaintance with the 

 subject. R. T. 



Das kleine botanische Practician fur Anfinger. Von Dr. 



Eduard Strasburger. Mit 114 Holzschnitten. (Jena, 



1884.) 

 A BOOK by Prof. Strasburger, entitled " Das botanische 

 Practicum," has recently been reviewed in Nature, and 

 recognised as a most valuable addition to botanical 

 literature. The same author has now produced a con- 

 densed edition of the same book under the heading given 

 above. The more important of the facts distributed 

 through the 600 pages of the first and larger edition are 

 here collected into the smaller space of 250 pages, an 

 arrangement which is obviously better suited to beginners. 

 It was specially remarked in the review of the larger 

 edition that the efficient study of the various types named 

 would occupy the average student a longer time than the 

 author of the book appeared to think. This smaller 

 edition will obviate the difficulty by supplying the ele- 

 mentary student with a shorter course of study, while the 

 larger book will no doubt be found more useful as a book 

 of reference for more advanced students, or as providing 

 a curriculum for those who will make botany their pro- 

 fession. The merits of good type and excellent illustra- 

 tions are to be found in this smaller book in as high a 

 degree as in the earlier and larger edition. F. O. B. 



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. 

 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 insure the appearance even 

 of communications containing interesting and novel facts.] 



Dr. Koch and the Comma-Bacterium 

 The article published in Nature of December 4, setting forth 

 Dr. Koch's well-known theories with regard to the connection 

 of a comma-shaped micro-organism with cholera, serves very 

 efficiently as the text for one who desires to point out the 

 deficiencies in Dr. Koch's observations and reasonings on this 

 subject. The article is the most favourable statement which can 

 be made on the side of those who accept Dr. Koch's conclusions, 

 and is to a certain extent not quite fair to his opponents, since 

 his original statements are not clearly separated from the subse- 

 quent statements which he has made in reply to criticisms. 



In opposing Dr. Koch's conclusions, it is desirable at the very 

 first to state clearly that those who accept them appear to labour 

 under two important misconceptions, the first being that Dr. 

 Koch is, and has been for a long time, acquainted with every 

 form (and the complete history of every form) of Schizomycetes 

 or Bacteria existing, whether in the healthy body or in disease, 



