Mr. Frost on the Mustard Tree of the Scriptures. 95 



two facts prove the analogy between the properties of the genera 

 Phytolacca and Sinapis. Linnaeus, in his Materia Medica, points 

 this out very clearly. 



It appears that the mustard tree of the Scriptures is undoubtedly 

 a species of Phytolacca, most probably P. dodecandra of Linnaeus. 

 I cannot be quite positive as to the species, as the plant which is 

 the subject of this communication has not yet flowered. 



29th August, 1825. 



Observations on an Emetic Oil termed " Pinhoen Oil." 



An expressed oil has just been sent to me from the Brazils, under 

 the name of Pinhoen oil. It is used there as an emetic, and acts 

 powerfully in the small dose of one or two drops. 



It appears to be procured from the seed of a species of Jatropha, 

 of which there are several indigenous to South America, most 

 likely J. multifida, the fruit of which has been long known 

 under the appellation of the French Physic-Nut. From some ex- 

 periments which I made about two years since on the seeds of 

 several species of Jatropha, I am inclined to think that there can 

 be but little doubt of the plant which yields this emetic oil being 

 of the genus just mentioned. And it may here be remarked, that 

 the expressed oil of the seed of very many species all produce 

 emetic and cathartic effects ; the former attended by a sensation 

 of heat about the fauces, and by doubling the dose, drastic pur- 

 gative effects ensue. 



Mr. Reeves, of Canton, informed me that the varnish which the 

 Chinese are so famous for making for covering paper boxes, tea 

 chests, 4*0., is formed by boiling the expressed oil of the seeds of 

 Jatropha curcas, with oxide of iron. The seeds of J. curcas have 

 frequently been mistaken for those of Croton tiglium, only, one 

 can suppose, from there being a degree of analogy between their 

 effects, as there is none in point of appearance. 



