90 Chronicles of Science. | Jan., 
prepared from cocoa-nut shell condensed the largest amount of the 
various vapours he experimented with. These included the vapours 
of water, bisulphide of carbon, common alcohol, methylic and 
amylic alcohols, benzol, ether, and chloroform, and of these the 
vapour of methylic alcohol was most freely absorbed. It was re- 
marked that the absorption of vapours by charcoal is always termi- 
nated in a much shorter time than in the case of permanent gases. 
At the next meeting (Noy. 16), a paper “‘ On Nitro-compounds, 
with remarks on Isomerism,” by Dr. Mills, was read. ‘The paper 
gave an account of the author’s examination of the alpha and 
beta varieties of nitrobenzoic acid, with especial reference to the 
action of hydriodic acid upon them, the difference in their behaviour 
to this agent being considered to indicate a difference between the 
nitryl radicals they contain. The author also pointed out a differ- 
ence in the behaviours of naturally formed benzoic acid, that obtamed 
from gum-benzoin, and the acid procured artificially, the former 
being nitrated with considerable difficulty, the latter with compara- 
tive ease. A mononitrated compound is ordinarily obtained with 
the natural acid, while the artificial yields a dinitro-compound. 
But on raising the energy of the attack by employing a mixture of 
nitric and sulphuric acids, the author obtained with ordinary ben- 
zoic acid a dinitro-compound, possessing characters nearly identical 
with those of the product formed by the action of nitric acid on 
toluol. In his remarks on isomerism, Dr. Mills controverted the 
view that isomeric substances are produced by variations in the 
position of some radical or radicals in the molecule, and expressed 
an opinion that the energy of the chemical reaction at the moment 
of the transfer of the nitryl radical conferred upon it specific func- 
tions, and thus accounted for the differences observed in the isomers. 
V. ENTOMOLOGY. . 
(Including the Proceedings of the Entomological Society.) 
Tre attention of the Entomological Society was, at its October 
meeting, directed by Dr. Wallace, of Colchester, to the cultivation 
of the Ailanthus silk-worm (Bombyx cynthia), and to the pro- 
bability of its becoming a lucrative occupation in this country. 
Ailanthus glandulosus, the food-plant of the insect, is a tree of 
remarkably quick growth even on the poorest soil, and the insects 
require no protection whatever, except from the birds. This year, 
from 18,000 eggs, he had obtained 5,000 cocoons. He had not 
yet attempted to wind the silk, but if this could be readily effected, 
he could see no difficulty to its successful cultivation, as all the 
necessary operations could be performed by children. “ Ailantine ” 
