So Copper obtainedfrom Iron , 
leaving its own Subttance inftead thereof^'. 
And this mott certainly is the Fa<tt, though 
the Dodtor feems to doubt it; the Purity of 
the Copper may be brought in Proof, and 
is not to be wondered at, for the minute 
Particles thereof, that floated in the Water, 
and were depofited in the Pores of the Iron, 
inuft neceffarily be lefs blended with fo¬ 
reign Matter than any Copper in its Ore 
can be. 
There are Copper Mines in the County 
of Wicklow in Ireland , called the Mines of 
Crone Bawm, or Corona Alba , on the North 
Side of the River Arklow , where the Water 
raifed from the Mines, that ufed to run 
away in Watte, has lately been converted 
to great Profit: for by placing Iron Bars 
on Beams of Timber fixed for that pur- 
pofe acrofs large Pits or Citterns, (floored 
with frnooth Flags and lined on the Sides 
with Stone and Lime) through which the 
Water runs, the Iron becomes incrufted 
in a few Days with Particles of Copper: 
which being fwept off from Time to Time, 
and falling to the Bottom, are, when a 
Quantity is collected, taken thence, in 
a fine brown Powder, confiding of Copper 
and the Ruft of Iron which affords, when 
# Vide Brown's Travels, 410, p. ttg. 
fmelted 
