104 Alum how and where produced : 
for a due Time, that Water when boiled, 
fufficiently in Pans of Lead (the Lees of Sea¬ 
weed AfHes called Kelp, and the Quantity 
of Urine being mixt therewith) produces 
Shoots of Alum , after Ifanding a few Days. 
But as fuch Shoots are feldom clean enough 
at fife: for Sale, they commonly are wafh- 
ed with or diffolved again in Water freed, 
from their Impurities, and fet to concrete 
a-new. 
Vail Quantities are made in Torkfloire 
and Lancajhire , mod: of the Hills between 
Scarborough and the River T'ees , as well as 
thofe near Prejion , abounding with this 
Mineral ; the Salts of which being diffolved 
and put into Adlion by the Moifture of the 
Air, if thereto expofed, without being cal¬ 
cin’d, the Mineral falls in Pieces, and yields 
a Liquor whereof Copperas or green Vitriol 
may be made *, 
Alum may alfo be procured from certain 
Earths by pretty much the fame Means. 
An Earth of this Kind now lies before me, 
which was brought from Africa , where a 
confiderable Trad of Land is faid to be of 
* At Altfettle in Bohemia are Mines of black Schijhis , 
whence they make great Quantities of Alum and Vitriol; 
and from a Gleba Pyritoja found in the fame Mines, they 
obtain much Sulphur. I am obliged to Dr. James Mounfey 
for this.Information ; and for Specimens of both the Sub* 
fiances, which he collected upon the Spot and fent me. 
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