IJ^Q SAKURAI: OONSTITUTIOX OF GLYCOCOLL. 



this body is not. an open-chain Compound, — -is not a c:ii'l)oxyhc com- 

 pound, or acid. 



A probable explanation of the facts, and one which gives every 

 support to the view of the cyclic constitution of the glycocolls seems 

 obvious to me. It is that while glycocoll itself appears not to form a 

 hydrate when dissolved, its derivatives do form such I13 drates, and 

 these aMition compounds will be, as pointed out in my paper, open- 



chain compounds. Oi'dinarv betaïn, for example, is, bv universal ad- 



X(CH3),-CH, 

 mission, NrCHOaOH.CIL.COOH, and anhv<lrons belain | | 



^ ^ ■ " () — CO. 



I am not aware whether the electrical conductivity of betaïn has been 

 determined or not, but it will doubtless prove to possess a rather high 

 dissociation constant. Glycocoll hy(h"ochloride, an undeniable open- 

 chain compound, was, some years ago, found by Dr. Walker himself 

 to be an electrolyte. 



Electrical conductivity of glycocoll derivatives must, then, be 

 regarded as most prol^ably due to their forming addition compounds 

 ^vith water and their subsequent dissociation, but there is nothing to 

 show that these derivatives are themselves open-chain compounds. 

 On the contrary, the non-conductivity of glycocoll rather points to its 

 being close-chained (even in solution), and by analogy we may regard 

 its derivatives as being also ring compounds. 



I must, therefore, maintain with added force that all facts, 'physical 

 as well as chemical, so far as known, point exclusively to the cyclic 

 constitution of the glycocolls as the one in every way to be preferred. 



