Foreign Vegetables. 293 
moniack (as it is called) is a concreted Juice of a 
middle Nature between a Gum and a Refin. It is 
fometimes in large Glebes compofed of fmall Grumes, 
of a brownifh Colour, with white or reddifh Spots 
interfperfed through its Subftance, fo as to refemble 
the Mixture in the Benzoinum amygdaloides . Some- 
times it comes to us in denfe, folid Tears, not un- 
like Frankincenfe, of a yellowifh or brown Colour 
on the Outfide, and white or inclining to yellow 
within, and fhining. It has a fweet Tafte when firft 
taken into the Mouth, which afterwards becomes 
bitter, and a penetrating Smell, fomething like Gal- 
banum, but ftronger. It foftens in the Hands, becomes 
dudtile under the Teeth, and grows whiter upon 
chewing. Being thrown upon burning Coals it 
takes Flame *, and is foluble in Vinegar, or hot 
Water. It is brought to us from Alexandria in 
Egypt, 
For internal Ufe the Tears are preferred to the 
Glebes. The belt are large, dry, and free from 
Impurities. The Glebes likewife, when clear and 
interfperfed with granular Spots, are approved. If 
they have any Mixture of Filth, they are purified 
by being diflolved in Vinegar, and then {trained and 
Lnfpifiated. But by this Preparation the Gum is 
greatly deprived of its volatile Parts. 
The pure Ammoniack in Tears Diofcorides calls 
S^au <rfx<», and that which is impure from a Mixture 
of Sand and Gravel, he calls < pvgocpoc . He tells us 
that it is the Juice of a Sort of Ferula , growing in 
that Part of Libya which lies near the Temple of 
Hammon . This Shrub, fays he, is called dyou rvXit. 
Pliny gives it the Name of Metopion, 
It is indeed evident that Gum Ammoniack is a 
milky Juice, flowing either fpontaneoufly or by In- 
cifion from a certain umbelliferous Plant not yet de- 
scribed. This we may conclude from the Seeds, 
U 3 which 
