Foreign Vegetables. 349 
leaved Convolvulus , otherwife called Convolvulus Sy- 
riacus , &cc. as above •, and that the Smyrna Scam- 
mony is the Scammony of Diofcorides and drawn 
from the Convolvulus folio hirfuto , the rough-leav- 
ed Convolvulus . This however he does not af- 
firm. Upon meeting with the ingenious Rotanift 
Doctor Sherard y and defiring to be fet right in this 
Point, he told me, that he himfelf had obferved 
the rough-leaved Convolvulus growing about Smyrna , 
but that no Juice is drawn from it ; becaufe the 
fmooth-leaved Convolvulus is fo common, that it 
yields more Juice than the Inhabitants have Occafi- 
011 for •, and that therefore they draw it only from 
fuch Plants as grow upon the Declivity of the Hill 
under the Citadel belonging to the Town. They 
make an Incifion into the Root, and apply to the 
Wound a Shell, in which the milky Juice is receiv- 
ed, and fet to dry. This Scammony in Shells is 
pellucid, of a whitifh or yellowifh Colour, like 
Refin or Glue •, but it is feldom or never fent into 
Europe *, the Scammony, which comes to us in 
Maffes from Smyrna , being brought thither, as we 
have before mentioned, from Cute and Cogni \ and 
the Merchants allure us, that in thofe Places it is 
got from the Convolvulus folio glahro , the fmooth- 
leaved Convolvulus . 
Diofcorides and Mefue have mentioned feveral Me- 
thods of obtaining this Juice, as well by Incifion 
as Expreflion ; and it is probable that the Scam- 
mony of the Shops is now obtained both Ways, 
which may be the Reafon why we find fo much Dif- 
ference in the fame Lump. 
Scammony, in a chymical Analyjis , affords firlt 
a fmall Portion of thin Liquor, fomewbat acrimo- 
nious, but giving no Marks either of Acid or Al- 
kali ; then a large Quantity of acid Liquor *, after- 
wards fome Liquor, botji acid and urinous ; and at 
