Aitg: 26, 1875J 



NATURE 



327 



types of Jife among the older formations he contended 

 to be no evidence in favour of development. It was 

 simply negative evidence, and could at any moment be 

 destroyed by the discovery of one positive fact in the 

 shape of a bone, tooth, or other fragment. No one could 

 make better use than he of such fortunate finds as that of 

 Dr. Dawson among the ancient carboniferous forests of 

 Nova Scotia, when from the heart of a fossil tree quite a 

 little museum of land-snails and lizard-like forms was 

 obtained ; or those which revealed such remarkable assem- 

 blages of little marsupial and other mammalian forms 

 from thin and local deposits like the Stonesfield slate 

 and Purbeck beds. But negative evidence, when multi- 

 plied enormously by observers all over the world without 

 any important contradiction, becomes too overwhelming 

 to be explained away. Though convinced of the un. 

 tenableness of the views of development which he 

 opposed, Sir Charles may have had his misgivings at 

 times that the yearly increasing and enormous body of 

 negative evidence in favour of the non-existence of higher 

 types of life in the earlier geological periods could not be 

 due to the mere accident of non-preservation or non- 

 discovery. At all events, when Mr. Darwin's views as to 

 the origin of species were made known. Sir Charles, 

 recognising in them the same basis of wide observation 

 and the same methods of logical analysis for which he 

 had himself all along contended in geology, at once 

 and zealously accepted them — a bold and candid act, 

 seeing that it involved the surrender of opinions which 

 he had been defending all his life. In no respect 

 did he show his remarkable receptive power and the 

 freshness with which he had preserved his faculty of 

 seeing the geological bearings of new truths more con- 

 spicuously than in the courage and skill with which he 

 espoused Mr. Darwin's hypothesis and proceeded at once 

 to link it with the general philosophy of geology. 



Of his work among the Tertiary formations, with the 

 nomenclature by which, through that work, they are now 

 universally known, his observations on the rise of land 

 in Sweden, his researches into the structure of vol- 

 canic cones, and other original contributions, over and 

 above the solid additions to science supplied by the 

 numerous editions of his popular works, it is not needful to 

 make mention here. Enough is gained if at this time these 

 few lines recall some of the services to which Sir Charles 

 Lyell devoted a long, honourable, and illustrious life, 

 which have graven his name in large letters on the front 

 of the temple of science, and in memory of which that 

 name will long be remembered with gratitude and enthu- 

 siasm as a watchword among the students of geology. 

 Archibald Geikie 



WATTS' DICTIONARY OF CHEMISTRY 



A Dictionary of Chemistry and the Allied Branches of 

 other Sciences. By Henry Watts, B.A., F.R.S., &c. 

 Second Supplement. (Longmans, Green, and Co., 

 1875.) 



'H'^HE appearance of the second supplement to Watts' 

 J- " Dictionary ^of Chemistry " is an event in the 



history of chemical literature which will certainly be 



ekomed by all English chemists. Although it may be 



said with truth that no great generalisations have been 

 made of late years in chemistry, the science is neverthe- 

 less advancing with gigantic strides so far as the accumu- 

 lation of facts is concerned. Perhaps no science possesses 

 such an extensive journalistic literature as Chemistry ; 

 month after month the journals of the Chemical 

 Societies of London and Berlin, the Gazzetta Chimica 

 Italiana, the Annalender Chetnie, Poggendorff's Amialen, 

 the Annales de Chemie, the proceedings and transactions 

 of the various learned Societies, as well as numerous 

 smaller chemical publications, all contribute to the vast 

 store of facts already recorded. It is not to be wondered, 

 then, that during the nine years which Mr. Watts devoted 

 to the compilation of his dictionary, the science should 

 have continued its growth at such a pace that the 

 author found it necessary to promise on the completion 

 of the work (Preface to Vol. V., 1869) a supplementary 

 volume bringing the record of discovery down to the 

 existing state of knowledge. The first supplement ac- 

 cordingly appeared in 1872, bringing the history of the 

 science down to the end of 1869. The volume now before 

 us carries the record of discovery down to the end of 

 1872, and includes some of the more important discoveries 

 made in 1873 and 1874. 



From the contents of the present supplement we cannot 

 select more than a few of the longer articles for notice 

 here. 



Turning first to the article on benzene, one cannot fail 

 to be struck with the rapid growth of our knowledge of 

 this body and its derivatives within the last few years. 

 The list of haloid, nitro-haloid, &c., derivatives has been 

 considerably increased since the publication of the last 

 supplement by the discovery of new isomeric modifi- 

 cations of these bodies — modifications the discovery of 

 which cannot but be regarded as signal triumphs to 

 chemical theory when we call to mind the fact that the 

 impetus given to the study of benzene, the fundamental 

 hydrocarbon of the aromatic series, arose from the theo- 

 retical speculations of Kekuld and his school. 



The subject of capillarity is treated of with consider- 

 able detail in an article some nine pages in length. The 

 development of this subject is due to the researches of 

 Quincke, Karmarsch, Buliginsky, Valson, and others. 

 The article on chemical action contributes much of im- 

 portance to the subject : we may particularly mention 

 Mill's researches on the co-efficient of chemical activity, 

 the numerous researches by Berthelot, in conjunction 

 with Jungfleisch on the division of a body between two 

 solvents, and with St. Martin on the state of salts in 

 solution ; likewise Favre and Valson's experiments on 

 crystalline dissociation. Passing on to the cinchona 

 alkaloids, we find that three new substances— quinamine, 

 paricine, and paycine — have been added to the list by 

 Hesse. The " constitution " of these cinchona alkaloids 

 is among the problems still awaiting solution at the hands 

 of chemists — may it not be hoped that the synthesis of 

 quinine will one day — as that of alizarine — be a chemical 

 possibility? In electricity, the chief additions to our 

 knowledge are Becquerel's experiments on electro- capillary 

 action, Quincke's theory of electrolysis, and Guthrie's 

 experiments on the relationship between heat and electri- 

 city. The mechanical theory of gases has developed into 

 a separate article of considerable importance in our eyes. 



