40 PHILOSOPHICAL TRANSACTIONS. [anNO 1756. 



his modesty would not permit him to subscribe his name to it, a series of veiy 

 curious and useful obser\^ations on the vegetable poisons growing in England ; 

 the knowledge of which could not be too much or too generally inculcated. 



The plants described in this account were disposed according to the 

 sexual system of Linnaeus : but our author had not contented himself with a 

 simple arrangement of the plants, the subject of his work ; he had gone further, 

 and had given not only the synonyms of some of the best authors, but, as far as 

 his reading and observations had enabled him, their medical and economical 

 uses, and their places of growth. 



Nothing could more tend to the advancement of the natural history of this king- 

 dom, than that persons conversant in the various parts of it, should collect the 

 productions of their own neighbourhood, and transmit accounts of them to the 

 R. s. How much correspondence of this kind had already done, nothing could 

 give a stronger testimony than the Synopsis Stirpium Britannicarum of the late 

 Mr. Ray ; as this, joined to his own industry, enabled Mr. Ray to commu- 

 nicate to the public a more perfect account of the plants of this country than any 

 other nation had then seen. 



[Then follows the catalogue of Leicestershire plants, which it was deemed un- 

 necessary to reprint, after the complete arrangement and descriptions of English 

 plants by Hudson, Withering, and Snnth.] 



CXII. An Attempt to Ascertain the Tree that yields the Common Varnish used 

 in China and Japan ; also to Promote its Propagation in our American Co- 

 lonies ; and to Rectify some Mistakes Botanists appear to have entertained 

 concerning it. By Mr, John Ellis, F. R. S. p. 866. 



As Mr. E. had a favourable opportunity, from his situation opposite to Mr. 

 Christopher Gray's nursery garden at Fulham, to examine his curious collection 

 of exotic plants, he began with the rhus, or toxicodendron, in order to clear up 

 some points disputed in two letters, lately published in the last volume of the 

 Transactions, Art. 27. One from the Abbe Mazeas, on the discovery of the 

 juice of certain species of toxicodendron staining linen of a fine black colour, 

 and the other, in answer to it, from Mr. Philip Miller, of Chelsea, insisting 

 that it was not a new discovery. 



To be satisfied o( the fact ; Mr. E. made several experiments on the 3 species 

 of toxicodendrons, mentioned by the Abbe Mazeas ; and found that their 

 juices do stain black, and, if fixed by alum, are not to be washed out by soap, 

 or boiling in a lye of pot-ashes : but the pinnated one, called by the gardeners 

 the poison ash, did not strike so deep a black as the other two trifoliate ones, 

 being more of a rusty colour. 



He went next on the inquiry, to comj^aic, and see, whether in reality this 



