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mation of ammonium-carbonate, the carbonic acid being resorbed 
from the air. There is no doubt that this resorption takes place; 
and expecting that the salt mentioned might cause the ripening, I 
added 10 pCt. carbonate of ammonium to the solution. However 
without the desired result, even after the solution was several 
months old. 
I then took into consideration whether the carmine might perhaps 
resorb oxygen from the air, and would need to be oxygenated; and 
this proved to be case. 
When putting together: 
10 gr. carmine powder, 
10 ee. ammonia, 
20 ee. hydrogenperoxyd, 
the mixture boiled for a short time in a glass receiver, then cooled 
down (for instance by letting the receiver float in water in a half- 
filled cylinderglass), a ripe carmine solution is obtained in a few 
minutes, which, treated in the above-mentioned way, produces fully 
9 gr.+) of an almost black ammoniumearmine, which is entirely, 
sometimes a little unclearly, soluble in water. 
Instead of boiling with hydrogen-peroxyd an equal quantity of 
a 1 pCt. solution of kaliumpermanganate can be taken as well, 
although in this case the oxygenation is easily carried too far. 
Physics. — “The entropy of radiation” (II). By J. D. VAN DER 
Waats Jr. (Communicated by Prof. H. G. VAN DE SANDE 
BAKHUYZEN). 
TNC 
Distribution of the vibrations of the molecules. 
In the second part of his “Vorlesungen über Gastheorie’ Prof. 
BOLTZMANN discusses the way in which the intramolecular energy 
is distributed over the different molecules. He finds that the chance 
1) If dry carmine has been used. But carmine as it is sold, frequently contains 
10 pCt. or more water, though it may seem to be dry. 
