190 



SCIENTIFIC THOUGHT. 



the master of the great German chemists of the middle 

 of the century. Mitscherlich at Berlin and Wohler at 

 Gottingen belonged to the school of the former, whereas 

 Liebig had the good fortune to be introduced through 

 Humboldt into Gay-Lussac's laboratory at Paris as the 

 first pupil/ 



and criticisms in breaking down the 

 older oxygen theory of acids in fa- 

 vour of Davj^'s more general views, 

 based upon his recognition of chlo- 

 rine and iodine as elementary bodies. 

 His handbook of Chemistry, as well 

 as his ' Jahresbericht ' (from 1820), 

 probably did more than any other 

 publications for the diifusion of ac- 

 curate chemical information. 



^ Liebig has himself, in an auto- 

 biographical memoir published post- 

 humously, so fully described the 

 merits of the two schools, and at 

 the same time given such a vivid 

 picture of the truly scientific s^Dirit 

 which animated German universi- 

 ties at that time, that I am tempt- 

 ed to give here some extracts. Of 

 his studies in Paris he says : " What 

 influenced me most in the French 

 lectures was their inner truthfulness 

 and the careful omission of all mere 

 semblance of explanations : it was 

 a complete contrast to the German 

 lectures, in which, through a pre- 

 ponderance of the deductive pro- 

 cess, the scientific doctrine had quite 

 lost its rigid coherence. ... I re- 

 turned to German}' (1824), where, 

 through the school of Berzelius, 

 ... a great reform had already 

 begun in inorganic chemistry. . . . 

 I always remember with pleasure 

 the twenty - eight years which I 

 passed at Giessen : it was, as it were, 

 a higher ])rovidence which led me 

 to the small university. At a large 

 university, or in a larger town, my 

 powers would have been broken up 

 and frittered away, and the attain- 

 ment of the aim which I had in 



view would have been much more 

 difficult, if not impossible ; but at 

 Giessen all were concentrated in 

 the work, and this was a passion- 

 ate enjoyment." " The necessity of 

 an institute where the pupil could 

 instruct himself in the chemical art, 

 by which I understand familiarity 

 with chemical operations of analysis 

 and adroitness in the use of appar- 

 atus, was then in the air, and so it 

 came about that on the opening of 

 my laboratory . . . pupils came 

 to me from all sides. . . . The 

 greatest difficulty presented itself, 

 as the numbers increased, in the 

 practical teaching itself. In order 

 to teach many at once, an ordered 

 plan was required and a progres- 

 sive way of working, which had 

 to be thought out and tried. . . . 

 A very short time had sufficed for 

 the celebrated pupils of the Swedish 

 master to give to mineral analysis 

 ... an admirable degree of per- 

 fection. . . . Physical chemistry 

 . . . had through the discoveries 

 of Gay-Lussac and Humboldt, . . . 

 and of Mitscherlich, . . . gained a 

 solid foundation, and in the chemi- 

 cal proportions the edifice appeared 

 to have received its coping-stone. 

 . . . No organic chemistry . . . then 

 existed ; Thenard and Gay - Lus- 

 sac, Berzelius, Prout, Diibereiner, 

 had indeed laid the foundation of 

 organic analysis ; but even the 

 great investigations of Chevreul on 

 the fatty bodies received for many 

 years only scant attention. Inor- 

 ganic chemistry still absorbed too 

 many, and indeed the best, forces. 



