216 
organism used by us has been another form than that employed by 
Pasteur in his classic experiment and the continued investigations 
of one of us?) (H. J. WarerMan) have exactly demonstrated that the 
phenomena of growth are dependent in a high degree on the variation. 
Delft. Laboratory, Org. Chem. Techn. High School. 
Chemistry. — “On a method for a more exact determination of 
the position of the hydroxyl groups in the polyoxycompounds”’. 
(4th Communication on the configuration of the ring systems).’) 
By Prof. J. Borsexen. (Communicated by Prof. A. F. Hor.LeMAN). 
The investigations as to the action of the polycompounds on the 
conductivity of boric acid were started to furnish a contribution to 
our knowledge as to the situation of the carbon atoms, and the 
groups attached thereto, in benzene. 
This object has been attained to a certain extent, but, in addition, 
the measurements have also taught us something about the position 
of the hydroxyl groups in the saturated polyvalent alcohols. 
The influence of polyoxycompounds and boric acid on each other 
has been known for a long time. 
So, for instance, the increase of the acidic properties of boric acid 
by means of glycerol was made use of in the titration of that acid 
and, reversely, the large increase in rotation exerted by boric acid 
on mannitol went to demonstrate that this polyatomic alcohol was 
indeed optically-active *). These few empirical data were very con- 
siderably added to by G. Macnanini*); at the same time an experi- 
mental foundation was given to the surmise that these phenomena 
might be due to the formation of compounds. 
He demonstrated that mannitol strongly increased the electric con- 
ductivity power of boric acid and that, although to a less extent, 
this was also the case with oxy-acids such as tartaric acid, salicylic 
acid, lactic acid, glycerine acid, gallic acid, mandelie acid and gly- 
collie acid. He thus proved the formation of complex ions, conse- 
quently of a chemical combination between the two components. 
Van ’t Horr ®, on. account of these investigations, was of opinion 
1) H. J. Waterman. These Proc. 29 June 1912, p. 124. 
2) Recueil 30, 392; 31, SO and 86. 
3) Vienon. Ann. Chim. Phys. 5e S. Il 433. (1874). 
4) Gazz. chim. 20, 428; 21, II, 134, 215. Zeitschr. phys. Chem. 6. 58. 
5) Lagerung der Atome im Raume. 3e Ed. p. 90. 
