( 462 ) 
suggested this paper. This pupil, called van Erprcum, said that he 
had observed that a glass filled to the brim with water and floating 
ice, does not flow over, when the ice melts. 
This fact leading easily to the law of the permanent level and 
this law — as the writer is bound to believe — having up to 
now escaped the attention of physicists, physical science owes the 
discovery of a remarkable fact and the addition of a paragraph to 
this pupil. 
Amsterdam, Dec. 1904. 
Chemistry. — “On _ trinitroveratrol’. By Dr. J. J. BLANKSMA. 
(Communicated by Prof. H. W. BaKnuis RoozrBoom). 
It has been previously stated *) that the dimethylether of trinitro- 
pyrocatechin is formed by the nitration of the dimethylether of 3.5 
dinitropyrocatechin. As the nitro-group might have been introduced 
either in the position 4 or 6, it was still necessary to ascertain the 
constitution of this compound. The substance which melts at 146°— 
147° is identical with trinitroveratrol, which has already been des- 
eribed by Tremann and Marsmoro ®) and is obtained by nitration of 
veratrol (the dimethylether of pyrocatechin) or of veratrie acid. 
Tiemann and Matsmoro have shown that veratrie acid on nitration 
yields nitroveratrol and nitroveratric acid. Afterwards, ZINCKm and 
Francke *) have proved that nitroveratrie acid formed by nitration 
of veratric acid has the following constitution: 
OCH, 
Zo NOCH 
xsd 
ONS 
COOH. 
Now, on further nitration with fuming nitric acid this nitroveratric 
acid yields trinitroveratrol so that the constitution of trinitrovera- 
trol is 
OCH, 
7 OCH 
teu 
NO,\ ANO, 
NO,. 
1) Recueil 28, 114. 
2) Ber. 9, 937. 
5) Ann. der. Chem. 293, 175. 
