589 



molecule of sulfanilic acid and hippuric acid each compensate the 

 action of something less than 1cm' of 'J ,06 normal NaOH-solution. 

 In alkalic solution thej act piacticallj as monobasic acid. 



The mentioned acids practically have no influence on the inversion 

 of sucrose by hydrochloiic acid (IIP). 



This gives rise to the supposition for sulfanilic acid in alkalic 

 solution ot the "open" constitution-formula, in acidic solution of the 

 "closed" formula. 



Dordrecht, August 1917. 



43 



Proceedings Royal Acad. Amsterdam Vol XX. 



