October 12, 1893] 



NATURE 



563 



appear to us that there is much advantage in thus divid- 

 i ing the responsibility in a small text-book which does not 

 , contain any original or speculative matter of importance ; 

 and in our opinion the reader would have gained had the 

 German original been freely edited by the translator, 

 who should have borne the entire responsibihty for the 

 English edition. 



The arrangement of the material is much the same as 

 in most previous works on this subject, but the descrip- 

 tion of a larger number of micro-organisms, considering 

 S; the size of the book, is attempted. In this matter the 

 Ij time has now come for a new departure, for with the con- 

 f| tinual additions to the number of known bacterial forms, 

 :» it is both impossible and undesirable that the descriptions 

 J? of all of them should find place in the body of a text- 

 * book. For the purpose of illustrating the principles of 

 1^ bacteriology, comparatively few forms need be described 

 9 in detail, whilst for an account of those forms which 

 are of secondary importance, special works should be 

 consulted, A work of this kind, which endeavours to 

 describe in the tabular form, every micro-organism 

 hitherto discovered, fortunately already exists in the shape 

 of Eisenberg's " Bakteriologische Diagnostik" (Hamburg 

 and Leipzig, 1891), so that the necessarily brief and im- 

 perfect descriptions of bacteria which are to be found in 

 small text-books, like the one under review, become worse 

 than valueless, inasmuch as they take up space which 

 should be devoted to the discussion of general principles. 

 Now, in this latter particular the work before us is 

 specially weak ; not only is the preliminary chapter on 

 the " general morphology and biology of micro-organisms" 

 very scanty, but the introductory rhatter at the com- 

 mencement of the several chapters is generally also quite 

 inadequate. Thus, for instance, in the chapter on the 

 micro-organisms of soil we find no less than two pages 

 devoted to the description of such obscure and unimpor- 

 tant forms as bacterium mycoides roseum, b. radiatus, 

 spinosus, liquefaciens tnagnus, sdssiis, and Clostridium 

 fcetidum^ whilst there is absolutely no mention of the 

 bacteria producing nitrification, nor of the organisms oc- 

 casioning the tubercles in leguminous plants, which are 

 of such enormous importance, both from a practical and 

 theoretical point of view. 



In that portion of the book devoted to the practical 

 methods, we find very ample descriptions of the 

 mechanical details for staining bacteria, but the account 

 given of the principles upon which these methods rest is 

 very meagre, and often betrays much ignorance of che- 

 mical principles in general. Thus, what are we to think of 

 the statement that '■^aniline oil s^ndi phenol are the mor- 

 dants {sic) most used in bacteriological research " .' Surely 

 a few words from a competent chemist would be calcu- 

 lated to put some order and arrangement into the wilder- 

 ness of empirical staining recipes with which the student 

 is confronted, and would prevent such inaccuracy in the 

 use of old-established technical terms. A mistake of 

 more practical importance, which a little chemical 

 knowledge again would have rendered impossible, is the 

 statement on page 20, that plates intended for culture 

 may be sterilised " after being cleansed with alcohol 

 and corrosive sublimate" ; in this case, however, we are 

 inclined to believe that the "alcohol" being placed i5i?/ortf 

 instead of after the "corrosive" sublimate must be a 

 NO. 1250, VOL. 48] 



lapsus plumcB which has failed to receive correction in 

 th« proof. 



Of the same order, again, is the statement that some 

 bacteria " cause a sphtting-up of urea into ammonium 

 carbonate" ; surely if the reaction in question, and which 

 consists in the adding on of two molecules of water, 

 CN„H40-l-2H20 = CN„H80s 



Urea Water Aroraonium 



Carbonate, 



can be described as " a splitting up," the addition of 

 two chimneys to a house might as logically be called a 

 disruption of the building ! 



The author in his preface states that " conformably to 

 the scope of a hand-book like the present, all references 

 to the literature have been omitted," but the names of 

 investigators have been freely introduced in the text, and 

 in some cases they have been selected apparently with- 

 out a due knowledge of the literature. Thus, from the 

 text (p. 124 and p. 156) it would appear that it is to 

 Rubner and Kirchner that we are indebted for the dis- 

 covery of the great bacteriological efficiency of the soil 

 as a natural filtering medium, whilst we were certainly 

 under the impression that Pasteur, not to mention others, 

 showed the bacteriological purity of spring and deep 

 well waters before the names of the above gentlemen 

 were known to the scientific world. In the same way the 

 discovery of the increase in the efficacy of chemical dis- 

 infectants by moderately raising the temperature is 

 ascribed to Heider, whilst it was really first made by Dr. 

 Wynter Blyth, some eight years ago, but his paper, which 

 was published in the Proceedings of the Royal Society, 

 was doubtless unknown to both Heider and the author of 

 this book ; but the translator might, in the interests of 

 British science, have seen that the papers in that and 

 other English media of publication had received their 

 due. In the chapter on Morphology we find no mention 

 of the researches of Ray Lankester and others on the 

 polymorphism of beggiatoa, which are of such interest 

 in connection with those phenomena of variation in both 

 the form and function of bacteria which are now begin- 

 ning to receive the serious attention of investigators ; nor 

 is there, indeed, any special reference to this subject of 

 variation, which at the present time is certainly one of 

 the most important in the whole domain of bacteriology. 

 A considerable part of the translator's appendix is 

 devoted to the bactericidal action of light ; here again we 

 think that the work of the original discoverers, Downes 

 and Blunt, has been inadequately appreciated, for these 

 investigators practically explored the whole subject in out- 

 line, and the more recent researches have principally 

 consisted in a confirmation of their results, and in filling 

 in details ; thus they showed that the bactericidal action 

 of sunlight is independent of rise in temperature, that the 

 most refrangible rays of the spectrum are the most active, 

 that their effect, moreover, is highly favoured if not en- 

 tirely dependent on the simultaneous presence of oxygen, 

 and, further, that the bacteria may be destroyed by light 

 in the absence of any culture-medium, but that they are 

 more resistant to light when immersed in water or very 

 dilute culture material. Again, we find no reference 

 to one of the most interesting recent additions to our 

 knowledge of this subject, viz. the discovery by Laurent 

 that exposure to sunlight causes some chromogenic 



