1168 
In Fig. 4 the results are again represented graphically with the 
limit value of the sol N°. 1 as unit. The result agrees well with 
what was expected, only the limit values for K. exhibit an unmis- 
takable depression with increasing sulphide concentration. We must 
for the present refrain from trying to explain this remarkable 
anomaly. 
6. The experience gained during the above described research 
has given rise to a number of questions; fresh experimental series 
started with the intention of answering those had to be postponed 
on account of the present circumstances. Hence, we can only point 
to some provisional results. 
We feel convinced that on boiling an As,S, sol an enlargement of 
the particles really takes place (light absorption, ultramicroscopic 
image, depression of the limit value of the Al--ion). At the same 
time it appeared that, on boiling, the particles do not become 
enlarged equally, but that the boiled sol contains particles of all 
sizes and that a fractional precipitation seems possible. This fact 
has, up to the present, only been recorded in the case of colloidal 
sulphur *), but does not seem to be a specific property of that colloid. 
The frequently recorded dependence of the value limit on the 
previous history becomes more comprehensible by these experiences. 
Further researches concerning all the above cited questions, as to 
the density of the sols (on which we already carried out a few 
series of measurements) and other correlated problems must be 
postponed till more peaceful times. 
Utrecht. van ’r Horr-Laboratory. 
Chemistry. — “Action of sodium hypochlorite on amides of a-oxy- 
acids. A new method for the degradation of sugars. By 
R. A. Wuherman. (Communicated by Prof. FrANcHrMONr). 
‘(Communicated in the meeting of February 27, 1915). 
g y ) 
In a previous communication *) a method was described by me 
for the degradation of amides of «-} unsaturated acids to the alde- 
hydes containing one atom of carbon less. 
It now seemed possible to degrade in the same manner the amides 
of a-oxyacids. The experiment has confirmed this supposition. 
1) Sven Open, Der kolloide Schwefel, Upsala 1913. 
2) Proc. 1909; more fully in Liepia’s Annalen 401, 1 [1913]. 
