FOXGLOVE. 335 



produces a copious dark violet precipitate with nitrate of silver *. 

 By distilling the aqueous extract Destouches obtained a consi- 

 derable quantity of carbonate of ammonia ; the presence of 

 which is also detected in the dry powder, and in the tincture, 

 which becomes milky by the addition of water, M. Leroyer, 

 of Geneva, has succeeded in isolating the active principle of 

 Foxglove, which he has named DigitaUne. He treated the 

 leaves first w'ith cold ether and then with the same agent heated 

 in a close stove. The extract procured by evaporating this 

 tincture had a resinous appearance and an insupportably bitter 

 taste, and produced a sensation of numbness on the tongue. It 

 was then dissolved in distilled water, hydrate of protoxide of lead 

 being added to neutralize the acid it contained, and evaporated to 

 dryness. The product was again treated with highly rectified 

 ether, and again evaporated. The residuum thus obtained was 

 a brown heavy substance, very deliquescent, scarcely crystalliz- 

 able, and extremely energetic. One grain of it killed a rabbit, 

 without producing convulsions, in a few minutes f. 



Poisonous Properties. — Cattle in general leave this plant 

 untouched. Both the leaves and seed prove fatal to turkeys \ ; 

 and a domestic fowl, to which the powder was given for some 

 days together, experienced a remarkable loss of plumage §. 

 Mongiardini states that animals are more sensible of the dele- 

 terious effects of Digitalis, in proportion as their stoinach ap- 

 proaches in structure to that of man. The celebrated Orfila 

 has made several experiments on dogs v.ith the dried leaves of 

 Foxglove, 



He gave six drachms of the powder to a strong dog and tied the oesophagus. 

 In two hours the animal made eiforts to vomit, and foamed at the mouth ; 

 shortly after he was seized whh. vertigo, uttered plaintive cries, and laid 

 down on his side. Three hours subsequently he was still able to walk, 

 but staggered very much. These symptoms increased in intensity, and he 

 died in the night. The stomach contained nearly all the powder ingested, and 

 the mucous membrane was covered with briglit red spots. The aqueous 



* Thomson's Dispensatory, 1836, p. 336. 

 -f- Magendie's Formulary, translated by Gregory, p. 201. 

 J Salerne, in Hist, de I'Acad. 1748, p. 84. 



§ 8chiemann, Diss, de Digitali purp. 31 ; see also Pennant, iu I'hilos. 

 Trans, vol. bcxi, P. i. p. 10. 



