CHARACTER AND WORK OF LIE BIG. 53 



Comptes Rendus, a very remarkable paper on the changes which are 

 produced in the power of thinking and observing by age. Fourcroy, 

 the great animal chemist, who, in connection with Vauquelin, laid the 

 foundation of that physiological chemistry on which the modern sci- 

 ence is based ; then Gay-Lussac, Thenard, and Dulong, men of the 

 new science, who continued the work in a most glorious manner, which 

 in this country had been carried to such a glorious issue by Humphry 

 Davy these men were at that time teaching at Paris, and at the 

 laboratory which the liberality of the first Napoleon and his envy 

 of English discoveries had established at L^cole Polytechnique. 

 They contiued to study and shape the new science which was destined 

 to give to the modern science of chemistry precision. 



Liebig then worked with Thenard, listened to Gay-Lussac's lectures, 

 and he met there the young German chemists, Runge, well known by 

 his many researches on tar, and the tar products; Mitscherlich, the 

 discoverer of isomorphism and polymorphism ; Gustav Rose, the 

 representative of the perfection of analytical and inorganic chemistry. 

 In 1823 he brought his first paper on the fulminates of silver and 

 mercury before the Academy. And now, let me quote to you what 

 he says of that event in the first work which he ever published. In 

 the preface, which is a dedication to Alexander von Humboldt, he 

 says that at the meeting of the Academy, on the 28th of July, 1823, 

 he had read his paper, and was just engaged in packing up his appa- 

 ratus and pi-eparations, when a man, one of the members of the Acad- 

 emy, approached him, entered into conversation with him, and in an 

 incredibly short space of time knew how to elicit from him all his 

 hopes, schemes, and intentions. He did not dare to ask, either from 

 shyness or from accident, who the gentleman was who spoke to him, 

 and he disappeared again among the academicians. But he says : 

 " From that day all the doors of society, and of all institutions, were 

 open to me. I did not know until many years afterward to whom I 

 owed this introduction and favor." It was to Humboldt, who had so 

 well recommended him to the great French chemists that Gay-Lussac, 

 who never took any pupil whatever into his laboratory, accepted him 

 as his only pupil, and, more than that, joined with him in his continu- 

 ation of those researches which at that early age he had brought to 

 such perfection. This preface is beautiful in its conception and feel- 

 ing, and has been printed in all the seven editions of the work which 

 have since been published. If there were time this would, perhaps, 

 be the place to show the wonderful influence which Humboldt has 

 exercised upon the science of all countries ; but I must pass over 

 that subject, and continue the account of Liebig's life. 



Through the recommendations of Humboldt and Gay-Lussac, both 

 of which were addressed directly to the Grand-duke of Hesse-Darm- 

 stadt, Liebig was, at the age of twenty-one years, by the supreme will 

 and absolute power of the grand-duke, appointed first Professor of 



