223 
One of them, represented by (I) must, in consequence of the 
favourable position of the hydroxyl groups (a) and (A), influence the 
conductivity more forcibly than the other one and because in aqueous 
solution they are converted into each other up to a definite equili- 
brium, the conductivity must decrease until this equilibrium-mixture 
is attained. 
In the other represented by II the conductivity must increase 
until the same limit value is attained. | 
The preliminary measurements executed by Mr. C. E. KLaMEr now 
have led to the result : 
1. That a-dextrose had, at 25°, a considerable positive influence 
on the conductivity. 
2. That this decreased slowly so as to attain a definite limit 
value after 24 hours. 
3. That the positive influence of g-dectrose (up to the present 
not obtained in a perfectly pure condition) was much slighter than 
that of a-dextrose. 
4. That it kept on increasing slowly to finally reach nearly, but 
not quite, the same limit value as in the case of the a@-dextrose. 
After repeated recrystallisations the conductivity of a 6.5°/, solution 
of «-dextrose at 25° was on an average 5 <6~®, of a 15°/, solution 
7x< 10-5, that of a 6.5°/, solution of g-dextrose obtained by recry- 
stallisation from pyridine 1010 ©, presumably it still contained 
a little pyridine. | 
The increase of the conductivity caused by a 
6.5 °/, a-dextrose solution on 2'/,°/, H,BO, = 42 X 10-6 
falling to oo. < 10-8 
The increase of the conductivity caused by a 
15°/, a-dextrose solution on 2'/, °/, H,BO, = 106 « 10-6 
falling to 90 >< 10 
The increase of the conductivity caused by a 
6.5 °/, B-dextrose solution on 2'/,°/, H,BO, = 20 10-6 
rising to 29 10 
Without anticipating the result of the final measurements with 
the sugars we may safely conclude that this method which, of course, 
is capable of extension in many directions can give us further data 
as to the more delicate structure of the molecules. 
In other respects also, the formation of complex compounds of 
boric acid with organic polyoxycompounds is of great importance. 
We know that boric acid is used as an antiseptic; this is based 
on the retarding action which this substance exerts on the growth 
of moulds. 
