Penfyhania, Philadelphia. 139 



pea. It is greatly to be wiflied that none of the 

 fhips, which annually depart from New Tork or 

 Penfyfoania, may bring them into the European 

 countries. From hence the power of a {ingle 

 defpicable infedt will plainly appear; as allb, that 

 the ftudy of the ceconomy and of the qualities of 

 infers, is not to be looked upon as a mere paf- 

 time and ufelefs employment.* 



THE Rhus radicans is a flirub or tree which 

 grows abundantly in this' country, and has in 

 common with the ivy, called Hedera arborea, 

 the quality of not growing without the fupport 

 either of a tree, a wall, or a hedge. I have feen. 

 it climbing to the very top of high trees in the 

 woods, and its branches fhoot out every where 

 little roots, which faften upon the tree, and as it 

 were enter into it. When the ftem is cut, it 

 emits a pale brown fap of a difagreeable fcent. 

 This fap is fo (harp, that the letters and characters 

 made upon linen with it, cannot be got out again, 

 but grow blacker the more the cloth is wafhed. 

 Boys commonly marked their names on their linen 

 with this juice. If you write with it on paper, 

 the letters never go out, but grow blacker from 

 time to time. 



THIS fpecies of Sumach has the fame noxi- 

 ous qualities as the poifonous fumach, or Poifon- 

 tree, which I have above defcribed, being poi- 

 fonous to fome people though not to every one. 

 Therefore all that has been faid of the poifon- 

 tree is likewife applicable to this j excepting that 



* IF the peafe were fteeped, before they are fown, in a lye of 

 lime water and fome diflblved arfenic, the pupa or aurelia of th* 

 infect would be killed. F. 



the 





