THE PROGRESS OF SCIENCE. 



573 



Hoff; the theory of electrolytic dis- 

 sociation to Arrhenius; and the theory 

 of the voltaic cell to Nernst;- but it is 

 Ostwald who has taken these theories, 

 has developed them and has forced the 

 world to accept them. No one else 

 could have fought the good fight as 

 Ostwald has done. He has founded a 

 distinct school, the Leipzig school as it 

 is sometimes called. A large majority 

 of the active physical chemists of to- 

 day have Avorked in Ostwald's labora- 

 tory at one time or another; but his 

 influence is not confined to his pupils. 

 There is probably no man living whose 

 opinions have so much immediate 

 weight in the world of chemists as does 

 that of Ostwald. 



Ostwald's record during the last 

 twenty-one years is an extraordinary 

 one, whether judged by quality or 

 quantity of work. The first edition of 

 the ' Lehrbuch der allgemeinen Chemie ' 

 consisted of two substantial volumes; 

 but it is dwarfed by the second edition 

 which runs to over thirty-four hun- 

 dred pages and is not yet finished. 

 The other books on chemistry include 

 a short introductory volume on phys- 

 ical chemistry, a laboratory manual of 

 physical chemistry, a history of electro- 

 chemistry, a volume on the scientific 

 principles underhung analytical chem- 

 istry, a text-book of inorganic chem- 

 istry, and an elementary book in dia- 

 logue form. All this is in addition to 

 lectures, laboratory work and editorial 

 duties. This last item is a serious one, 

 because a large percentage of the 

 papers published in the Zeitschrift fur 

 physikalische Chemie come from Ost- 

 wald's laboratory and because he re- 

 views all the new books, and has, until 

 the last few years, written critical re- 

 views of many of the current articles 

 on physical-chemical subjects appear- 

 ing in other journals. Over and above 

 this, Ostwald is the editor of a series 

 of reprints of important chemical 

 papers. 



Mention has already been made of 

 the fact that Ostwald at one time gave 

 lessons in music and painting. As 



results of this we have an unpublished 

 course of lectures on the theory of 

 harmony and a book on painting. 

 Every year Ostwald spends a large 

 part of his vacations in sketching, 

 using a modified form of pastel which 

 is his own invention. 



A very natural result of Ostwald's 

 literary work in chemistry has been his 

 growing interest in the theory of 

 knowledge. Beginning as an ardent 

 admirer of Mach, he has devoted more 

 and more time in recent years to phi- 

 losophy. With characteristic energy 

 he has started a journal of philosophy 

 and has published in book form a 

 course of lectures on philosophy de- 

 livered in Leipzig in 1901. It must 

 be admitted that Ostwald ranks higher 

 at present as a chemist than as a phi- 

 losopher; but it was as a philosopher 

 that Ostwald attended the Interna- 

 tional Congress of Arts and Science at 

 St. Louis, and he is to lecture at Har- 

 vard both on chemistry and on philos- 

 ophy. 



THE ECLIPSE OF TEE SUX. 



A total solar eclipse is an event 

 which appeals in equal measure to the 

 scientific investigator and to the pop- 

 ular imagination. Yet the interest is 

 not only different, but to a certain ex- 

 tent conflicting. The astronomer is 

 concerned with certain technical prob- 

 lems, such as the composition of the 

 corona, which have less connection with 

 human welfare than most scientific 

 questions. The popular interest is 

 largely due to the awe-inspiring char- 

 acter of the event, a survival perhaps 

 from the time when this was the occa- 

 sion of portents and omens. It may be 

 assumed that the simple explanation of 

 the moon's shadow will gradually do 

 away with the apparent marvel of this 

 phenomenon, though the accuracy with 

 which it can be foretold will continue 

 to impress the unlearned with the 

 wonders of the science, which has been 

 called both ' the queen of the sciences ' 

 and the ' science of pure curiosity.' 



The eclipse of August 30 was for 



