7^ A N G L 
Co. of Macclesfield, applied to Sic Nicholas for a leafe of 
Penrhyn ddu mine in Caernaryonfhire; with which they 
were, much againft their wills, compelled to take a leafe 
of part of this mountain, and to carry on a level, and 
make a fair trial. The trial was accordingly made ; ore 
was difcovered ; but the expences overbalanced the pro¬ 
fits. They continued working to great lofs ; and at length 
determined to give the affair up. They gave their agent 
orders for that purpofe ; but he, as a final attempt, divi¬ 
ded his mefi into ten feveral companies, of three or four 
in a partnerfhip, and let them fink {hafts in various places, 
about 800 yards eafhvard of a place called the Golden Ven¬ 
ture, on a prefurnption that a fpring, which ifflted from 
near the place, inuft come from a body of mineral. His 
conjefture was right; for in lei's than tv/o days they met 
with, at the depth of feven feet from the furface, the fo- 
lid mineral, which proved to be that vail body which, has 
lince been worked to filch 'advantage. The day that this 
difeovery was made was March 2, 176S : which has ever 
fine! been obferved as a feftival by the miners. Soon af¬ 
ter this difeovery, another adventure was begun by the 
]< ev. Mr. Edward Hughes, owner of part of the moun¬ 
tain, in right of Ills wife Mary Lewis, of Llys Dulas; fo 
that the whole of the treafure is the property of Sir Ni¬ 
cholas Bayley and himfelf. The body of copper-ore is of 
unknown extent. The thicknels has been afeertained in 
fome places by the driving of a level under it, feveral 
years ago, and it was found to be in Come places twenty- 
four yards. The ore is moftly of the kind called by Cron- 
fted Pyrites cuprijlavo viridefeens, and contains vafl quanti¬ 
ties of fulphur. There are other fpecies of copper-ore 
found here. Of late a vein of the Pyrites cupri grijeus of 
Cronfted, about feven yards wide, has been difcovered 
near the weft end of the mountain: fome is of an iron grey, 
fome quite black; the firft contains i6ib. of copper per 
cwt. the laft forty. An ore has been lately found, in form 
of loofe earth, of a dark purplifli colour; and the beft of 
it has produced better than eight in twenty. Some years 
ago, above thirty pounds of native copper was found in 
driving a level through a turbery ; fome was in form of 
mofs, fome in very thin leaves. 
“ It is quarried out of the bed in vaft malTes; is broken 
into fniall pieces; and the mod pure part is fold raw, at 
the rate of about 3I. to 6i. per ton, or fent to the fmelt- 
ing-houfes of the refpedfive companies to be melted into 
metal. The more impure ore is alfo broken to about the 
fize of hens eggs ; but, in order to clear it from the quan¬ 
tity of fulphur with which it abounds, as well as other 
adventitious matter, it muft undergo the operation of burn¬ 
ing. For that purpofe it is placed between two parallel 
walls of vaft length: fome kilns are twenty, others forty 
and fifty, yards in length; fome ten, others twenty, feet 
wide; and above four feet in height. The fpace between 
is not only filled, but the ore is piled many feet higlier, in 
a convex form, from end to end. The whole is then co¬ 
vered with flat ftones, clofely luted with clay ; and above 
is placed a general integument of clay, and frnall rubbifli 
of the work, in order to prevent any of the fumes from 
evaporating. Of late, fome kilns have been conftruded 
with brick arches over the ore, which is found to be the 
beft method of burning. Within thefe few years, attempts 
are made to preferve the fulphur from flying away; and 
that is done by flues made of brick, whole tops are in form 
of a Gothic arch, many fcores of feet in length. One end 
of thefe opens into the beds of copper which are to be 
burnt. Tliofe beds are fet on fire by a very fmali quantity 
of coal, for all the reft is effected by its own phlogifton. 
'The volatile part is confined, and dire fled to the flues; 
initscourfe the fulphureous particles firike againft their 
roofs, and fall to the bottom in form of the fineft brim- 
ftone ; which is collected and carried to adjacent houfes, 
v here it is melted into what is called in the fliops Jlone 
Ixrimjlone. 
“ The beds of copper, thus piled for burning, are of 
vaft extent. Some contain 400 tons of ore, others 2000. 
E S E Y. 
The firft require four months to be completely burnt, the 
laft near ten. Thus burnt, it is carried to proper plaqes 
to be dreffed, or wafhed, and made merchantable. By 
this procefs the ore is reduced to a fourth part in quantity, 
but confiderably improved in quality: and by this means 
the water is ftrongly or richly impregnated with copper, 
which is ditfolijed by the acid quality of the fulphur ; and 
is collected or precipitated again by iron in the above de- 
feribed pits. The iron is all diflolved. 
“ But a far richer produce of copper is difcovered from 
the water lodged in the bottom of the bed of ore, which is 
highly faturated with the precious metal. This is drawn 
up, eith.er by means of whimfies or windmills, to the fur- 
face, and then dillributed into numbers of reCtangular pits 
thirty-fix feet long, fome pits more l'ome lefs, twelve to 
fifteen feet broad, and twenty inches deep. To fpeak in 
the language of the adept, Venus muft make an afttgna- 
tion with Mars, or this folution will have no effed. In 
plain Englifh, a quantity of iron muft be immerfed in the 
water. The kind of iron is of no moment; old pots, 
hoops, anchors, or any refufe, will fuffice ; but of late, 
for the convenience of management, the adventurers pro, 
cure new plates, four feet long, one and a half broad, and 
three-quarters of an inch thick. Thefe they immerfe in¬ 
to the pits. The particles of copper inftantly are preci¬ 
pitated by the iron, and the iron is gradually diffolved into 
a yellow ochre. Great part of it floats off by the water, 
and finks to the bottom. The plates, or the old iron (as 
it happens), are frequently taken out, and the copper 
feraped off; and this is repeated till the whole of the iron 
is confirmed. The copper thus procured differs little from 
native copper, and is prized accordingly, and fold for 
prices of 25I. to 45I. a ton. This difeovery is far from 
new : it lias been pradifed long in the Wicklow mines in 
Ireland; and above a century in thofe of Hern-grundt in 
Hungary, where it is called ziment copper. The waters of 
the Hungarian mines are much more ftrongly impregnated 
with copper than thofe of Parys mountain. The firft ef¬ 
fects its operation in twelve or about twenty days, the laft 
requires two months. Horfe-fhoes, iron made in the fliape 
of hearts, and other forms, are put into the foreign wa¬ 
ters ; and, when perfectly tranfmuted, are given as pre- 
fents to curious ftrangers. 
“Nature hath been profufe in beftowing her mineral fa¬ 
vours on this fpot: for above the copper-ore, and not 
more than three quarters of a yard beneath the common 
foil, is a bed of yellowifii greafy clay, from one to four 
yards thick, containing lead-ore, and yielding from 600 
to 1000 pounds weight of lead from one ton; and one ton 
of the metal yields not lefs than fifty-feven ounces of fil- 
ver. This place has been worked for lead-ore in very dif- 
tant times. In the bottom of the pool was found an an¬ 
cient fmelting-hearth of grit-ftone, and feveral bits of 
fmelted lead, of about four inches in length, two In 
breadth, and half an inch thick. Thefe works have ad¬ 
ded greatly to the population of the ifland ; for about 1500 
perfons are employed; who, with their families, are fup- 
pofed to make near 8000 perfons, getting their bread from 
thefe mines.” 
Near Kemlyn Bay is a quarry of marble, common to 
this place, fome parts of Italy,, and to Corfica, and known 
in the fhops by the name of Verde di Corjica. Its colours 
are green, black, white, and dull purple, irregularly dif- 
pofed. In different blocks one or other of the colours are 
frequently wanting; but among the green parts are often 
found narrow veins of a mod elegant and filky white af- 
beftos. It is a compound fpecies of marble: part is cal¬ 
careous, and may be ailed upon by aqua-fortis. The 
green parts partake of the nature of jafper. It is apt to 
be interfeded by frnall cracks, or by afbeftine veins, there¬ 
fore incapable of taking a high polifti. This quarry lies 
on the lands of Monachty, in the parifli of Llan-Fair- 
Ynghornwy; and it is found again in the ifle of Skerries, 
off this parifli. In Rhofcolyn parifli, a green amianthus, 
or brittle albedos, is met with in great plenty in a green 
■2 marble 
