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as happens in Woodrafhes. Befides, thefe Herbs have 
tew or no fulphureous or acid Parts, like moft Woods } 
and the Pot-afh made of them has few of thefe Prin- 
ciples in it, like what is made of Wood. 
It is however generally faid, if we bum our Wood 
in a clofe Place, as a Kiln in which we bum Lime, 
or make Charcoal, or a Pit dug in the Ground, wc 
may impregnate the Afhes with the fulphureous 
Fumes and acid Parts of the Wood, only by the 
Ciofenefs of the Place, or by fmothering the Fire 
in it. If at the fame time we impregnate them 
with a greater Quantity of lixivial Salt, it will flux 
the whole Mafs, and make it run into a folid hard 
Confidence like Pot-afh. This is commonly direfted^ 
to be done, by throwing frefli or green Wood or 
Herbs upon the others, as they are burning, before 
they are quite reduced to Afhes ? or by fmothering 
the Fire, as in making Charcoal? and at the fame 
time to fprinkle the Allies, thus burnt, with a ftrong 
Lye from time to time, in the manner commonly 
prattifed with Glafswort. 
This would be a more ready Way of making Pot- 
afh than any of the above-mentioned? but as thofe 
who give their Advice about it, have neither tried 
it, nor feen it done ; and thofe who have tried this 
or any other Way, find more Difficulty in it, than 
they at firft imagined, wc ffiali fufpend our Judgment 
about it, till we fee it fairly tried, left wc fhould 
deter fome from making ufcful Experiments of it, 
or lead others into fruitlefs and expenfive Attempts. 
By the various Ways of making Pot-afh above- 
mentioned, and the different Materials it is made 
ef, there appear to be many different Kinds of it, 
Dddd 2 that 
