dit' Summe derersten Hauptunterdeterminanten 2// — 1'"' Grades jeder 

 Hauptunterdetenninante 2»"" Grades der symmetrischen Determinante 

 gleieh Null ist derjenigen Beschaffenheit der schiefen symmetri- 

 schen Determinante aequivalent ist. dass alle Hauptunterdetermi- 

 nanten 2n — V" Grades derselben «deich Null sind. 



2. M. LÉON MAIfCHI.EWSIvI m. c. Przyczyna biernosci optycznej wodnych 

 raztworöw kvr. antiwinowego. (The cause of optical inactivity of 

 aqueous solutions of antitavtaric acid). (Sur les causes de l'inac- 

 tivité optique des solutions aqueuses dt l'acidi antitartrique). Note présentée 

 dan« la Séance du 1 Décembre 1902. 



The optical inactivitv et" solutions of antitartaric aeid has heen 

 explained hitherto by supposing that the actions on the polarised 

 light of the two symmetrica! halves of the molécule are diametrically 

 opposed although numerically equal. Thtre takes place, as the phrase 

 goes, an internai compensation of the opposed actions of the right 

 and left asymmetrical earbon atoms contained in the same molé- 

 cule, as eaeh half of the molécule is the mirrored image of the other. 



»Such an explanation may indeed hold good as long as we deal 

 with solutions of antitartaric acid prepared by using solvents which 

 do not cause eleetrolytical dissociation. For aqueous solutions how- 

 ever this explanation cannot be applied. Antitartaric acid. being 

 a bibasic acid. will no doubt split up into the ions: 



C(X> 



! 



Il C-OH 



I 

 Il-C-OH 



COOH 



and H 



and considering that one of the conclusions to be drawn from the 

 researches by Landolt. Oudemans. Eykman. Colson, Pri- 

 bram. K recke and others is that the ions of an active tartaric 

 acid cause stronger rotation than the undissociated molécules, it 

 follows tliat each of the two halves of the monovalent antitartaric 

 acid ions is not a mirrored image of the other. 



