^ ( 764 ) 
^^f. The Neigbhouruig foil difFcrs little from other grounds 
with us, having neither coiinncn Sal, nor K iter in it ; for though 
therebea Saic-well with us, jet it is both on the other fidcof 
Ijr^^, and a confiderable di fiance from the fire. 
I o. Whether Kcar the places that bear Sal armoniac, th(re he Any 
Springs that participate of that ingredient or of fome other fuhterra* 
ned fait f which will be bejl knorvn by a Jlow evaporation^^ cafe ene 
have not the conveniency to do it by dtftillation^ and thereby prefer ve 
both the afcending liquor and the Kemains.andby then confidertng the 
remaining fnbjlance^ in order to find whether Salarmoniac be impreg* 
nated with Mineral bodies not difcernable in it by the Colour^ Jnd 
there are fome^ther Mineral Salts^ that^ though white, are very dif- 
fering from allthe natural Salts that are commonly known ^ or that I 
have reud of in any Author. 
Anf. I have induftrioufly obfervcd the Springs that are near the 
Fire^ and find none of them that give ihe leaft fufpicionof Sa\ 
armoniac. The water that runs from the adjacent Colyeries is vi- 
iriolihe^ giving as deep a tinfture wich Galls as Scarborough Spaw. 
In a word, it differs nothing from the waters that ordinarily 
drown our Colyeries , and coft our Coal-owners fowuch to be 
quit of them. The other Springs, nioft of which aredry this year, 
are of ordinary ufe, containing no Mineral Salts in them : But I 
hope you will ceafe to wonder , that Coal Cbould produce ii vola- 
tile Salt by the aflion of fire, feeing I have gathered /^m^^^^wr 
from a burning Brick-kiln, where nothing but Clay and Coal is 
. burnt together, and I hope none will expeft the volatile Sale in 
the Sal armoniac from ordinary C!ay. The reafon^that firft prom- 
pted rac to feek this Salt there, was, that the Smell of the Kiin did 
fomewhat refemble that of the Subterraneal fire. There is alfo a 
fort of Mineral we call a 5'/^/^,which is partly Coal, partly Alum- 
ftone,partly Marcafite, which being laid up in heaps and burnt,are 
ufed for hardening the Coal-ways $ upon thefe heaps, whilfl burn- 
ing, I have cfcengaihered both Erimfione^vd Sal armoniac. 
As for the Experiment of pouring cold water upon the pou* 
dred Marcafite, the event was, that it produced a Vitrioline water, 
but no heac ; though I will not deny bm the Experiment may fuc^ 
ceed better, if more accurately handled by that Noble Philofo- 
pher who hath lately been furniflied with a confiderable quantity 
of Marcafttes from my worthy Friend and Aflbciate Dr. Vtsr ant s^dt 
greater quantity of which may be fent if need require ; for in 
little 
