172 



NATURE 



[June 23, 1898 



LONDON BIRDS. 

 Birds in London. By W. H. Hudson. 8vo. Pp. xvi 

 + 339; illustrated. (London: Longmans, Green, and 

 Co., 1898.) 

 A S a writer on the habits of animals and their natural 

 ^^ surroundings, and one, moreover, gifted with an 

 unusually facile and interesting mode of expression, Mr. 

 Hudson has already established such a reputation that 

 any new work from his pen is almost sure of meeting 

 with a favourable reception. And, in our opinion, the 

 present volume is as full of interest as the nature of the 

 subject permits ; many of his descriptions bringing into 

 prominent notice the amount of attraction to be found 

 in the open spaces in and around London if only we go 

 about with our eyes open, and can snatch a few half- 

 hours of repose from the business and pleasures of the 

 great city. Most of us, who either live in the country, or 

 spend our holidays there, quite fail to realise how glad- 

 some must be the sight of the bird-life in our London 

 parks to those who have little or no opportunities of 

 escape from the wilderness of bricks and mortar ; and 

 Mr. Hudson, in his enthusiasm for his subject, says that 

 not only do such glimpses brighten the existence of our 

 toilers, but that they are almost essential to such existence. 

 Be this as it m9,y, his description of the delight afforded 

 to our poorer neighbours by the contemplation of the 

 birds kept in the little enclosure at the eastern end of 

 the Serpentine is quite pathetic reading, and affords full 

 justification for all that is being done to encourage the 

 feathered denizens of our parks to remain and multiply. 

 From a scientific point of view the work, it must be 

 confessed, cannot lay claim to a high place ; and it was 

 doubtless not intended so to do. The decimation of the 

 species that formerly lived in and around London, and 

 the introduction, either natural or artificial, of extraneous 

 kinds, preclude it being considered as a manual of the 

 avian faun.\ of the district. Still even the scientific 

 ornithologist ought to find some interesting matter in 

 regard to the persistence of some species and the dis- 

 appearance of others ; and more especially so when he 

 finds that in some cases it is the apparently hardier and 

 bolder forms that have disappeared, and the more deli- 

 cate that have remained. Still more remarkable is the 

 recent colonisation of certain spots by such apparently 

 shy and retiring species as the dabchick and moorhen. 



In some ways, perhaps, the author is inclined to take 

 matters a little too seriously ; and, personally, we fail to 

 assent to his strictures concerning the rearing of wild 

 ducks on the Serpentine. If we read him right, he would 

 have them partly, if not entirely, disestablished in 

 favour of his pet species the crow. But, to our own think- 

 ing, it is a far more generally interesting, and certainly a 

 far less common sight to watch the evolutions of the 

 flights of duck on our park waters, than it would be to 

 observe the sedate manner of crows and rooks, which 

 most of us, if so disposed, can see elsewhere. Still more 

 uncalled for are the author's strictures on the annual 

 battue held to keep the numbers of the ducks within 

 proper limits. Somebody must undertake the duty ; and 

 if the duty be also a recreation, surely the Ranger or his 

 deputies should not be debarred from enjoying it. But 

 apparently Mr. Hudson is of opinion that nothing but 

 NO. 1495, VOL. 58] 



outdoor natural history is worth anybody's attention, 

 since he goes out of his way (p. 80) to attack the Govern- 

 ment for the purchase of the Blenheim pictures. 



Although there may have been reasons for their 

 removal unknown to the general public, our personal 

 sympathies are, however, decidedly with the author over 

 the felling some years ago of the elms in Kensington 

 Gardens, and the consequent total disappearance of the 

 rooks. 



Even to summarise the contents of the book would 

 largely exceed our limits to space, but attention may 

 especially be directed to the chapters devoted to the open 

 spaces on the outskirts of London, and to the two on 

 the protection of birds in our parks, and on those most 

 suitable for encouragement or introduction. In the last 

 of these the author is strongly of opinion that water- 

 fowl, if properly protected, will return to their assigned 

 haunts to breed, adding :■ " I believe that our ornamental 

 water-fowl ought never to be pmioned except in the 

 cases of a few rare exotic species. When a bird is 

 pinioned its chief beauty and greatest charm are lost ; it 

 is then little more than a domestic bird, or a bird in a 

 cage." With this commendable sentence we take leave 

 of a very pleasantly written and charmingly illustrated 

 little book. R. L. 



OPTICAL ACTIVITY. 

 Das optische Drehungsvernwgen organischer Substanzen 

 und dessen praktische Anwendung. By H. Landolt, 

 assisted by Drs. O. Schonrock, P. Lindner, F. Schiitt, 

 L. Berndt and T. Posner. Second Edition. Pp. xxii 

 -1-655. (Braunschweig: Friedrich Vieweg und Sohn, 

 1898.) 



THE first edition of this book, which appeared nine- 

 teen years ago, has since its publication been the 

 standard work on the rotation of the plane of polarised 

 light by active substances. Since 1879, however, the 

 number of active substances known has increased from 

 300 to over 700, the methods of determining the rotation 

 have been much improved, and considerable advances 

 have been made in the theory of the asymmetric carbon 

 atom, to mention only a few of the directions in which 

 progress has been made. All this necessitated a thorough 

 revision of the " Drehungsvermogen" ; and in order to 

 cope, in reasonable time, with the mass of material, the 

 author has called in the assistance of the specialists 

 above named in writing several of the chapters. The 

 writers must be congratulated on the way in which they 

 have welded the different chapters into a homogeneous 

 whole, the disjointedness which so often arises from 

 such joint-authorship having been most happily avoided. 

 Comparitig the present edition with the former one, the 

 progressive broadening and consolidation of our know- 

 ledge of optical activity is very apparent. Twenty years 

 ago the main outlines of the subject were already 

 sketched in, and these remain practically unchanged ; how 

 much has been done in the interval, in filling in details, 

 can best be appreciated by reading the present work. 



The arrangement of the material remains very much 

 the same as in the former edition, but the revision has 

 been very thorough ; so far as we have been able to 

 judge, nothing of importance has been omitted. 



