222 
Proceedings of the Royal Society of Edinburgh. [Sess. 
jected gaultheria oil to the action of phosphorus pentachloride ; but, to 
his surprise, he obtained, after a vigorous action, both from the methyl and 
from the ethyl ether, a new chloride, “ chlorure de salicyle,” Cl ( ' ^ 
is obvious that Gerhardt did not distil the product as Chiozza had done, but 
drew his conclusion as to its nature only from the action on it of methyl 
and ethyl alcohol, by which it is retransformed into ethers of salicylic acid. 
Gerhardt does not quote Chiozza’s paper, nor does he discuss its contents. 
Gerhardt’s pupil, Drion, further extended Gerhardt’s experiments on sali- 
cylic ethers.* His observations are of interest to us here, as he describes 
the preparation of salicyl chloride somewhat more in detail than Gerhardt 
had done : — “ Le chlorure de salicyle que j’einploie pour la preparation du 
salicylate d’amyle a ete obtenu, pour la premiere fois, par M. Gerhardt, 
en faisant agir le perchlorure de phosphore sur l’huile de gaultheria. Dans 
cette reaction remarquable, il ne se forme que des traces d’oxychlorure de 
phosphore ; mais il se degage beaucoup d’acide chlorhydrique, et j ai 
constate egalement la production abondante de chlorure de methyle. Le 
chlorure de salicyle peut etre chauffe j usque vers 200 degres sans se 
decomposer, mais on ne peut le distiller. 
“ Dans le but de l’obtenir pur j’ai cherche a le distiller sous une pression 
moindre que celle de l’atmosphere. Bientot d’abondantes fumees d’acide 
chlorhydrique sont sorties de la poinpe et m’ont contraint de renoncer a 
l’emploi de cet appareil. J’ai continue la distillation sous la pression 
atmospherique, et j’ai recueilli dans le recipient un liquide fumant, pre- 
sentant tous les caracteres des chlorures organiques.” 
Treated with water, the distillate yielded a mixture of salicylic and 
chlorobenzoic acids, from which Drion concluded that the “ chlorure de 
chlorobenzoile, C 7 H 4 C10, Cl,” was formed by the decomposition of the 
“chlorure de salicyle.” “ Il avait ete obtenu deja par M. Chiozza en faisant 
agir le perchlorure de phosphore sur Tacide salicylique.” 
I sum up the collection of observations made in Gerhardt’s laboratory 
by Chiozza, Gerhardt, and Drion on the action of phosphorus pentachloride 
on gaultheria oil. The violent reaction of the two substances takes place 
with the evolution of hydrochloric acid and methyl chloride : only traces of 
phosphorus oxychloride are produced. The undistilled product of the 
reaction, when treated with methyl alcohol, gives methyl salicylate, and 
was therefore pronounced to be salicyl chloride, the acichloride of salicylic 
acid. But the supposed salicyl chloride cannot be distilled unchanged, 
either under ordinary or under reduced pressure. The product obtained 
* Comptes rendus , xxxix. 122-125, seance du lundi, 10 juillet 1854. 
