24: NOYES-POTTER— THE VALENCE OF NITROGEN [April 24, 



acid and that of the anhydride of a-aminocampholic acid. We 

 know that the latter compound contains a six-atom ring. 



Determinations of the molecular weights in aqueous solutions by 

 the freezing point method have shown that all four of the amino 

 acids are monomolecular in such solutions. 



The experimental details of the investigation will be published in 

 the Journal of the American Chemical Society. 



