Kekule and Kolbe

Abstract

I WRITE Kekule without an accent, as he was a descendant of old Bohemian nobles, the Kekule de Stradonice, whose ancestors, being Bohemian brothers, had to emigrate after the battle of the White Mountain (1620); it is he whom we thank for the reform of organic chemistry. As a man of Slavonic origin Kekule was a ‘romanticist’ and arrived at his doctrine of the chemical structure more by genial intuition than by experimental investigation (see Brauner; “Collection” II., 225). On the other hand, I agree with my old friend, Prof. Armstrong, who said in his excellent review (NATURE, May 31, 1930, pp. 807–810) that the rôle played by Kolbe in our science is often insufficiently appreciated. This is probably due to the circumstance that not all teachers of chemistry stick to the principle that special lectures on the evolution of chemical theories ought to be given to advanced students, as I did for many years. Kolbe was the type of a ‘classicist’ of German origin. His work was done under the influence of his great teacher, Bunsen, another ‘classicist’ I wish only to direct attention to the constitution of carbonic acid, C₂O₂^OHO_OHO, and its derivatives, which, though written in Gmelin's equivalents, was, according to my modest opinion, the first correct structural formula and in which the carbon atom C₂, translated into our modern views, appears as tetravalent. For the same reason it follows from his formula of sulphuric acid, S₂O₄^OHO_OHO, that it is a structural formula containing hexavalent sulphur. Both geniuses retain their value.