422 



SClEhCE. 



[N. S. Vol. XV. No. 376. 



the title, and if we take into consideration 

 the historic eminence of the subjects of the 

 lectures, as well as the fitness of the lecturers 

 for their biographical tasks and their success 

 in preparing them, it is safe to say that no 

 more important or fascinating contribution 

 to the history of chemistry has been issued 

 within the decade. In each case care was 

 taken to select as the lecturer one who had 

 been personally intimate with the deceased 

 chemist, or who was especially well qualified 

 to write of his researches with the sympathy 

 born of studies analogous to his; the result 

 forms an illustration of the international 

 character of science, for the native of Bel- 

 gium is portrayed as to his life and labors by 

 an American, the native of Switzerland by a 

 Swede, the Germans by Englishmen, a French- 

 man by another American, and only one lec- 

 ture, on a Swede, is by a compatriot. 



The methods followed by the lecturers in 

 dealing with the individuals assigned them 

 vary considerably, but the majority depict the 

 personality of the chemist, his domestic life, 

 his oificial duties, his positions of honor, and 

 after these his labors and discoveries in the 

 field of chemistry; in several instances the 

 biographer introduces valuable disquisitions 

 bearing on the theories which the person por- 

 trayed founded or helped to establish. Pro- 

 fessor J. W. Mallet, of the University of Vir- 

 ginia, writing of Jean Servais Stas, precedes 

 his account of the life-work of the Belgian in 

 the determination of atomic weights, with a 

 careful summary of the fundamental ideas 

 that gradually led up to the question, 'What 

 is the mass (or weight) of an atom of a par- 

 ticular element?'; and he presents a clear 

 statement of investigations as to the atomic 

 weight of the elements from the time of 

 Berzelius to that of Stas. At the beginning 

 of his painstaking researches Stas had an 

 almost absolute confidence in the accuracy of 

 Prout's hyiDothesis, but at their conclusion he 

 said, 'The theory of Prout must be considered 

 as a pure illusion.' Mallet himself, however, 

 seems inclined to believe that there may be 

 still something in it. 



In passing, let me say that the biographer 

 of Stas falls into the error of assigning to 



Wenzel a share in the discovery of the law of 

 neutrality, an error originating with Berzelius, 

 and often repeated, but corrected by J. S. C. 

 Schweigger, Angus Smith, Ladenburg and by 

 others. 



In his lecture on Marignac, the Upsala pro- 

 fessor, Cleve, introduces a skilful survey of 

 the complicated history of the rare earths, in- 

 cluding a table giving the characters of the 

 elements of the yttrium-cerium groups that 

 was highly esteemed at the date of its publica- 

 tion (1895). 



Dr. W. H. Perkin, in his sketch of the 

 labors of ITofmann, introduces an authorita- 

 tive account of the origin of the coal-tar color 

 industry, and both Drs. Japp and Thorpe in 

 their lectures on Keluile and on Victor Meyer, 

 respectively, insert most praiseworthy contri- 

 butions to the history of those branches of 

 organic chemistry in which each was laboring 

 so successfully. 



These disquisitions do not partake of pad- 

 ding, hvX are among the most valuable features 

 of this very valuable volume. 



One of the most difficult men to treat, on 

 account of his gigantic intellectual position, 

 Plelmholtz, is presented in a masterful way, 

 notable for its vigor and brevity, by Dr. Geo. 

 F. Fitzgerald. 



Dr. Percy Frankland's biography of Pasteur 

 is very readable and appreciative; he points 

 out that the French chemist long ago 'com- 

 pletely foreshadowed and grasped that im- 

 portant branch of our science which we now 

 call stereo-chemistry' as shown by the philo- 

 sophical reflections made by Pasteur after his 

 discoveries in connection with racemic acid. 

 Some bold experiments conducted by Pasteur 

 were designed to accomplish 'the task of turn- 

 ing the Creator's world upside do^vn'; one of 

 these was carried on at Lille in 1854. Fie had 

 a clock arranged with heliostat and reflector, 

 to reverse the natural movement of the solar- 

 rays striking a plant from its origin to its 

 death, so as to ascertain whether in such an 

 artificial world, in which the sun rose in the 

 west and set in the east, the optically active 

 bodies could be obtained in enantiomorphic 

 forms. Dr. Frankland reviews Pasteur's 

 studies on fermentation, his researches on 



