218 
1/, mol. protocatechuic acid had at 25° a specitic 
conductivity = W334i < 1G 
1/, mol. boric acid = Born 
Found a conductivity of the mixture = 817.75, 10-4 
Increase = 118.9 x 10-6 
1/, mol. of gallie acid had at 25° a spec. conductivity = 750.7 X 10-6 
il, ,, of boric acid 5 Ae 
Found for the mixture 917-6 XA 
Increase — 141.2 X 10-6 
From this influence on the conductivity we may conclude that 
with the polyoxybenzene derivatives an important reaction only then 
takes place when the hydroxyl groups are situated in the ortho- 
positions in regard to each other, 
Of a specific aromatic influence there can be no question because 
it would then be difficult to understand why resorcinol, hydroquinone 
and phloroglucinol do not exert an increasing action whereas mannitol, 
pentaerythrol and glycerol do increase the conductivity (MaGNaNINs, 
BÖESEKEN and van Rossem I. ¢.). 
We are constrained, as stated above, to look for the cause in the 
favourable situation of the hydroxyl groups in regard to the boric 
acid molecule. 
Now, the peculiar property of pyrocatechol and other orthodioxy- 
(and also of amido-oxy and diamido-) compounds of benzene and 
other ring systems to readily absorb another atom and to form with 
this, as a rule, very stable compounds has been known for a long time. 
This is attributed to the exceedingly ready 5-ring formation, there- 
fore to the favourable position of the ortho-placed groups. 
Without troubling, provisionally, about the configuration of the 
compounds formed between boric acid and the polyoxyderivatives, 
we may take it as very probable that an analogous cause determines 
their origin. 
The importance of demonstrating the influence of the polyoxy- 
compounds on the conductivity of boric acid is not related to the 
fact itself but lies in the sensitiveness of the method and its simple 
application. 
It enables us to announce the formation of compounds without 
having to isolate the same and even more: from the degree of 
influence we can draw important conclusions as to the position of the 
hydroxyl groups in the original polyoxycompound. 
If, for instance, we find that the increase of the specific conductivity 
at 25° caused by: 
