SCIENCE 



[Vol. IV., No. 74. 



CHARLES ADOLPH WURTZ. 



The subject of this sketch, Charles Adolph 

 Wurtz, who died on the 12th of May at Paris, 

 was the chief representative in France of what 

 is generally known as modern chemistiy. He 

 was born November 26, 1817, at Strassburg. 

 Here he began his studies, and received the 

 degree of doctor of medicine. Before his 

 graduation in medicine, he was made assist- 

 ant in the chemical department in the medi- 

 cal facuhvy ; in 1845 he became assistant in 

 Paris ; in 1846 he was made chemical direct- 

 or of the School of art and manufactures ; in 

 1851 he became professor in the Agronomic in- 

 stitution of Versailles ; and in 1854, after the 

 death of Orfila, he was elected professor of 

 medical chemistry, taking upon himself the 

 duties connected with the chair of pure chem- 

 istiy, up to that time held by Dumas, and that 

 of toxicology. In 1866 he was made dean of 

 the medical faculty, — a position which he held 

 until 1875, when he became professor of or- 

 ganic chemistr}* in the facuhry of sciences. 



Wurtz's contributions to chemistry are numer- 

 ous and important. He is fairly entitled to be 

 counted among those who have originated and 

 developed the views which are now held by 

 the majority of chemists. The two hypotheses 

 which at the present daj r form the basis of 

 speculation concerning chemical phenomena, 

 are, 1°, the hypothesis of Avogadro, according 

 to which equal volumes of all gases contain the 

 same number of molecules ; and, 2°, the valence 

 hypothesis, according to which the elementary 

 atoms differ among each other as regards the 

 number of atoms of other elements which they 

 can hold in combination. Thus we have the 

 compounds represented by the formulas, HC1, 

 H 2 0, and H 3 N, in which the atoms of chlorine, 

 oxygen, and nitrogen are represented in com- 

 bination with one, two, and three atoms of lrv- 

 drogen respectively. Before these differences 

 among the elements were recognized, the ex- 

 istence of various types of compounds was 

 observed. In a vague sort of way, compounds 

 were referred to this or that type : gradually, 

 however, the idea of types became more defi- 

 nite, and then, undoubtedly, exerted a great 

 influence on the development of chemistry ; 

 leading directly, as it did, to the conception 

 of valence. The first important investigation 

 of Wurtz had much to do with giving definite- 

 ness to the conception of types. In the paper 

 containing the results of the investigation, he 

 described certain compounds, which he regard- 

 ed as ammonia, in which one of the parts of 

 hydrogen was replaced by complex groups con- 



taining carbon and hydrogen ; as, CH 3 (methyl) 

 and C 2 H 5 (ethyl). Representing ammonia as 



N < H, the new substances can be represented 



(h 



( CH 3 ( C 2 H 5 



thus, N J. H , N J. H , etc. It became 



(h (h 



clear that substances can be made which bear 

 a very simple relation to ammonia ; and a good 

 experimental basis was furnished for referring 

 these compounds to the ammonia type. In 

 regard to this disco ver}*, Kekul6, the distin- 

 guished German chemist, says, "The discov- 

 ery of the bases corresponding to ammonia is 

 indisputably the corner-stone of our present 

 views." 



It is an extremely interesting fact, that Lie- 

 big predicted the discovery ten 3*ears before it 

 was made, in developing his views regarding 

 the nature of the nitrogenous bases, the alka- 

 loids ; but the view that these bodies can be 

 referred directly to ammonia in the sense in 

 which Wurtz regarded them was not gener- 

 ally accepted by chemists until shortly after 

 his discovery. 



Another important investigation of Wurtz 

 is that which led to the discover}^ of the so- 

 called diatomic alcohols, the chief of which is 

 glycol. Ordinary alcohol may be referred to 

 the water type in the same way that Wurtz's 

 bases are referred to the ammonia type ; i.e., it 



{XT 

 tj, in which one 



of the hydrogen atoms is replaced by the com- 

 plex group, ethyl, C 2 H 5 . According to this 

 view, which is founded upon experimental evi- 

 dence, alcohol is represented by the formula, 



O 



C 2 H 5 

 H 



In 1854 Berthelot's memoir on 



the fats and glycerine appeared. In this it 

 was shown that glycerine acts in general like 

 an alcohol, but that acids unite with it in three 

 proportions. Wurtz suggested .that just as or- 

 dinaiy alcohol may be regarded as derived from 

 water as above indicated, glycerine may be re- 

 garded as derived from water as represented 



{C H 

 H 3 5 . In other words, 



ordinary alcohol is derived from water b}' the 

 substitution of one group, C 2 H 5 , for one hydro- 



{TT 

 H ' 



whereas glycerine is derived from water by 

 the substitution of one group, C 3 H 5 , for three 

 atoms of hydrogen in three molecules of water, 



r 3 . This led Wurtz to inquire whether, 



O, 



