C 416 ] 
mortal poifon : fecondly, becaule, from the conflru6lion 
of its parts, gum is very ill adapted for having the acti- 
vity which violent poifon has ; and conhdering the fmall 
quantities in which myrrh is taken, and the opocalpajmn 
could have been but in an inconfiderable proportion to 
the myrrh, to have killed, it muft have been a very aCtive 
poifon. Thirdly, thefe accidents, from a known caufe, 
mull have brought myrrh into dilufe, as certainly as the 
Spaniards mixing arfenic with the bark, would banifli 
that drug when w'e faw people die of it. Now this never 
was the cafe: it maintained its character among the 
Greeks and the Arabs, and fo down to our days ; and a 
modern phyfician thinks it might make man immortal, 
if it could be rendered perfectly folublc in the human 
body. GALEN then was miliaken as to the poifonous 
quality of the opocalpajuni. The Greek phyficians knew 
little of the natural hiftory of Arabia; lefs hill of that of 
Abyliinia; and we who have followed them know no- 
thing of either. This gum being put into water fwells 
and turns white, and lofes all its glue; it refembles gum 
adragant much in quality, and may be eaten fafely. This 
fpecimen came from the Troglodyte country in the year 
1771: a piece of myrrh from Arabia Felix, and a piece 
of gum of the fajfa from Abyffinia were packed up 
in another feparate box to be fent you for comparifon, 
but forgotten by my fervant. They will be fent here- 
after. The the' tree which produces the opocal- 
P^ffuiriy does not grow in Arabia. Arabian myrrh is ea- 
fily known from Abyffinian by the following method: 
take 
