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Chemistry. — "O?; melting points in systems of optic isomers.'^ 

 By Prof. H. W. Bakhuis Roozeboom. 



Ill order to test' the views on melting points of mixtures of optic 

 isomers, as communicated in the Proceedings of the Meeting of Feb. 25"^ 

 1899, page 312, Mr. Adriaki has now in the first place examined 

 two examples in which the certainty existed of the inactive substance 

 being a racemic compound. 



The first example is the dimethylic ethereal salt of tartaric acid. 

 Here the d- and Mbrm have a lower melting point than the racemic 

 compound. 



The second example is the dimethj'lic ethereal salt of diacetyl 

 tartaric acid, where the d- and ^fürm have a higher melting point 

 than the racemic compound. 



For the present only the melting points of mixtures of d- and 

 r-forms have been examined in all their proportions. Consequently 

 we could only get the right half of fig. 3 and 4 (vide page 312). 



Yf e found : 



I. Dimethylic ethereal salt of tartaric acid. 



