(104 ) 



7. With a view of ascertaining whether a transformation was 

 also possible withont HCl, the ^-glucoside was kept for a long time 

 in a fused condition. After cooling the aj) appeared to be quite 

 unchanged. 



Zincchloride in methylalcoholic solution is also incapable of causing 

 the transformation. 



8. In conclusion it may be mentioned that the rotatory power of 

 a solution of methjlmannoside [of which glucoside only one form 

 is known as yet] in a solution of hydrochloric acid in methylalcohol 

 gradually decreases without formation of mannose. 



It seems natural to assume that this is caused by a partial change 

 into a (3-isomer which may, perhaps, also be isolated. 

 These investigations are being continued. 



Org. Cliem. Lab. University. Amsterdam, June 1903. 



Chemistry. ''The electrolytic conductivify of soliitio)is of Sodium in 

 mixtures of ethyl- or methylalcohol and water." By Mr. 

 S. T1.1MSTRA l>z. (Communicated by Prof. C. A. Lobry de Bruyn). 



In his study of the velocity of substitution of one nitro-group in 

 0- and p-dinitrobenzene by an oxyalkyl ^) Steger arrives at the result 

 that the reaction constants of o-dinitrobenzene and the two alcoholates 

 NaOCijHs and Ka OCH3 are not changed by dilution or by addition 

 of a sodium salt. On the other hand, in the formation of ethers, 

 these constants are increased by dilution, as shown by Hecht, Conrad 

 and Bruckner, and decreased by addition of a sodium salt as demon- 

 strated by Steger. 



Lobry de Bruyn pointed out that it would be necessary to inves- 

 tigate the conductivity of Na OC,H. in alcoholic solution. 



In a further investigation of the influence of water on the substi- 

 tution of the XO.^ -group in o-dinitrobenzene by an oxyalkyP) and on 

 the formation of ethers ') it appeared; l**' . that the velocity coefficients 

 of these reactions remained constant when water was added up to 

 an amount of 50 per cent by weight; 2"^. that the addition of water 

 decreased the velocity of reaction of Na OC,H. but increased that of 

 Na OCH3 (at least at the commencement, afterwards the velocity 



1) Dissertation, Amsterdam, 1898. Receuil 18, 13. (1899). 



2) Lobry de Bruyn and Alph. Steger, Receuil 18, 41. 



3) Lobry de Bruyn and Alph. Steger, Receuil 18, 311. 



