580 



3. It could be established by dehydration experiments of the 

 solid hydrate at different temperatures that this hydrate is a hydrate 

 of the «-modification. 



4. It was demonstrated by experiment that 93°.5 in the system 

 water-milksugar is no ordinary transformation point, but a point 

 that we propose to call a transition-dehydration point, as at this 

 temperature the hydrate of the «-modification under the pressure of 

 'J atm. dehydrates and is also converted to the ^Unodification. 



5. The observed phenomena have suggested that for nailksugar 

 two kinds of molecules a and [i have to be assumed, on account of 

 which the system water-milksugar must be considered to be pseudo- 

 ternary. Of this system the isotherms have been determined under 

 the pressure of 1 atm. at dififerent temperatures. By also indicating 

 the curve which represents the situation of the equilibrium between 

 a and [i milksugar at different total concentrations the situation of 

 the binary ecpiilibrium diagram at different temperatures could be 

 pointed out in the pseudo ternar} system, which enabled us to 

 explain in a simple way all the phenomena observed. 



6. Then the pseudo ternary ^'-^'-figure of the system H,0 -|- « 

 milksugar + |i milksugar with the surface of equilibrium lying in it 

 was constructed. 



7. A new theory was drawn up for the mutarotation, and in 

 conclusion it was still proved that the monohydrates in the sugar 



series cannot contain the group - — b y 



Amsterdam, June 29, 1917. Anorg. Chem. Laboratory 



of the University. 



