196 
POPULAR SCIENCE REVIEW. 
in which he shows that there are certain perfectly well-defined organic 
foodies which shine in the dark when they are in contact with an alcoholic 
solution of caustic potash. These foodies are : hydrobenzamide, amarine, 
lophine, and the crude product of the action of alcoholic ammonia upon 
foenzile : and to these the author now adds (“ Comptes Rendus,” Feb. 12, 
1877), paraldehyde (C 2 H 4 0) 3 , metaldehyde (C 2 H 4 0) w , aldehyde-ammonia 
(C 2 H 4 <T^^ 2 ), furfurine, C I5 H l2 0 3 N 2 , hydro-anisamide, ^ H 24 0 3 N 2 , 
anisidine, C 24 H 21 0 3 N 2 , hydrocinnamide, C 27 H 24 N 2 , and hydrocuminamide. 
He ascrifoes this chemical phosphorescence to the slow combined action of 
the caustic potash and the oxygen of the air, and the intensity of the phe- 
nomenon is in proportion to the slowness of the action. The bodies are either 
polymeric aldehydes, or products of the action of ammonia on the aldehydes, 
from which aldehydes can be produced either directly or by the absorption of 
the elements of water, and it is to the slow oxidation of the aldehydes in 
the nascent state that the author ascribes the phosphorescence of these 
bodies. 
Copper in Preserved Peas. — At the meeting of the French Academy of 
Sciences on February 12, M. Pasteur gave an account of the general results 
of an investigation made by him of the preserved peas ordinarily sold in 
Paris. Out of fourteen tins purchased at various shops ten were found to 
contain copper, sometimes to the amount of about yo^oo the total weight, 
deducting the liquid, which always contains much less than the peas. The 
copper becomes fixed, especially in an insoluble state, in the solid matter of 
the peas, particularly in the leguminous part beneath the outer envelope. 
According to M. Pasteur nothing is easier than to detect the presence of 
copper in preserved peas. All those which present anything of the green 
tint of natural peas contain copper, those which are free from the metal 
having a yellowish tint. Although there is a difference of opinion as to the 
extent to which salts of copper are poisonous, M. Pasteur maintains that the 
practice of employing that metal to improve the appearance of preserved 
peas ought to be absolutely proscribed ; and he suggests that if nothing more 
can be done the dealers in the articles so improved in appearance should be 
compelled to label their wares, “ Preserved peas , coloured green by salts o f 
■copper.” He thinks, and perhaps justly, that they would find comparatively 
few buyers. In connection with the question of poisoning by copper we may 
refer to an extraordinary statement made by M. Rabuteau to the Academy 
of Sciences at the meeting following that at which M. Pasteur spoke as 
above (“Comptes rendus,” February 19, 1877). M. Rabuteau noticed the case 
of a girl of 20 who took in the course of 142 days 43 grammes of ammoniacal 
sulphate of copper, and died of rapid tubercular disease three months after 
taking the last dose of the poison. The liver was analysed by M. Rabuteau, 
who found it to contain nearly 24 centigrammes of copper, its total weight 
being 1,474 grammes. Hence M. Rabuteau concludes that the salts of 
copper are far less poisonous than is generally supposed ; and especially that 
it would be exceedingly rash to affirm that we have to do with copper 
poisoning in cases where eight or even twelve centigrammes of copper 
are found in the livers of persons who have died under suspicious circum- 
stances. 
