134 AMERICAN JOURNAL 



" Moniteur " on this subject, M. Bourricaud showed how " the 

 enormously-increased demand for the green oysters of Marennes, 

 so justly renowned for their delicacy, had rendered the oyster 

 banks of that coast insufficient to supply the beds ;" how, 

 under these circumstances, it had become necessary to have 

 recourse to Spain, Brittany, England and Ireland ; and how the 

 young natives from Falmouth were not deemed presentable until 

 they had been subjected to about six months' sojourn in the com- 

 pany of their French brethren. Coming, after this prefatory 

 information, to the case in point, he related how a certain 

 tradesman, actuated by the lawless desire of premature ag- 

 grandizement, had been guilty of selling, in the market of 

 Rochefort, oysters from Falmouth, which had remained only 

 three weeks in the French beds. By a prompt analysis of the 

 remaining individuals belonging to this poisonous batch of 

 oysters, made by M. Cuzent, it was found that an average of 

 " twenty-three centigrammes (about 3| grains) of salt of copper 

 was yielded by a dozen of these oysters " — a dose which, as M. 

 Crosse remarks in the "Journal de Conchyliologie," is more 

 than sufficient to account for the evil effects which are said to 

 have manifested themselves. 



The presence of so extraordinary a product as copper in 

 these oysters was soon accounted for by the discovery that the 

 part of the Bay of Falmouth whence they were brought was in 

 the immediate vicinity of a mine of copper, then in process of 

 working. The waters which continually washed the bank being 

 strongly impregnated with the salts of copper, communicated a 

 similar seasoning to the oysters, which, thanks to their obtuseness 

 of organization, seem to have been very little affected by it 

 themselves, and to have become in some sort acclimatized. 



Very different, however, was the effect produced on the un- 

 suspecting dupes of the Rochefort merchant. According to all 

 accounts, it Avould appear to have been a veritable case of 

 poisoning, although, we believe, fatal consequences were 

 averted ; and, in spite of the assurances of M. Bourricaud, 

 that a "complete poisoning" by means of these oysters would 

 be impossible, we agree with the editor of the " Journal de Con- 

 chyliologie," that an incomplete one is a sufficiently disagreeable 

 affair. 



In order to ascertain the presence of copper in the oyster, 

 M. Cuzent recommends that a sufficient quantity of pure ammo- 

 nia be poured upon the flesh, which will soon declare its poison- 

 ous qualities by assuming the dark blue tint which distinguishes 

 ammoniacal salts of copper. Another method is to plunge a 

 sewing-needle into the green parts of the oyster, and immerse 



