n8 THE POPULAR SCIENCE MONTHLY. 



approbation in such a matter would be equally misplaced. . . . Every- 

 thing has been said upon the importance of high scientific training, 

 one of the treasures of the human mind. A great country should in- 

 crease it continually, in order to be able to diffuse it abundantly." 



Besides the multitude of papers embodying the results of his spe- 

 cial investigations, and his addresses, Professor Wurtz is the author of 

 a number of works of a more general character, among which are his 

 " Traite elementaire de Chimie medicale " (Elementary Treatise on 

 Medical Chemistry), 3 vols., Paris, 1864-'65 ; "Lecons elementaires de 

 Chimie modern e " (Elementary Lessons of Modern Chemistry), 1866- 

 '68 ; " Dictionnaire de Chimie pure et appliquee " (Dictionary of Pure 

 and Applied Chemistry), 1868 and following years, with an introduc- 

 tion published separately in 1868, under the title " Histoire des Doc- 

 trines chimiques " (History of Chemical Doctrines) ; " Les hautes 

 Etudes pratiques dans les Universites Allemandes " (High Practical 

 Studies in the German Universities) ; and an unfinished " Treatise on 

 Biological Chemistry" (vol. i, 1880). The "Dictionary" just men- 

 tioned, which was completed in 1879, after twelve years of preparation 

 and publication in numbers, is pronounced by the "Revue Scienti- 

 fique " the most complete treatise on chemistry now existing in France. 

 In its preparation, Professor Wurtz was assisted by his fellow-chemists 

 and compatriots, who contributed special articles, each working in the 

 line to which he had given the most attention. Professor Wurtz him- 

 self furnished the theoretical articles, especially those having reference 

 to the theory of atoms and their unitary grouping in compounds, of 

 which he is the leading expositor. " In these articles," says the " Re- 

 vue Scientifique," " the reader will recognize the vigor and precision 

 of style which are the stamp of the works of M. Wurtz." In English 

 translations have been published " Chemical Philosophy according to 

 Modern Theories " (London, 1867), and " Theory from the Age of La- 

 voisier" (1869). His two latest works, in their English translations, 

 have gained considerable circulation in the United States. The " Ele- 

 ments of Modern Chemistry " (1880) is a text-book, the leading feat- 

 ures of which are defined by a discriminating critic in " Nature " to 

 be " clearness of statement, selection of typical facts from among the 

 vast array at the service of the chemical compiler, and devotion of a 

 comparatively large space to chemical theory, and to generalizations 

 which are usually dismissed in a few words in the ordinary text-book " ; 

 withal, notwithstanding its copiousness, the book " is exceedingly in- 

 teresting and eminently readable." The "Academy," reviewing the 

 same work, speaks of its author as " universally recognized as one of 

 the most able of living chemists ; he is also an exact thinker, deeply 

 imbued with philosophical ideas, and a very successful teacher." The 

 book comprises a complete introduction to both inorganic and organic 

 chemistry, and presents the newest ideas regarding such subjects as 

 atomicity and isomerism. The other book, " The Atomic Theory," is 



