Eureka daily sentinel. [volume] (Eureka, Nev.) 1871-1887, 1877-02-03

so utb OF east; that is to say, running south o
east and north OF west; the dip of the hang
ing wall is steep, dipping north, or east O
north; the dip OF foot wall is quite ria Die
ID some places almost perpendicular, and ir
such places We do not expect to End or,
oodiesa ut other places it is quite fat, a DE-,
or even low +, and at such places we conf
IDENTITY expect to find bodies Of ore; ia arriv.
ing at an explanation as to the natural phe-
nolnena. observed in course of exploration
we can proceed by one of two methods, viz
First, to assume a theory, and then make ouI
facts tally with it; or, far better, examine all
the facts, and then deduce a theory from
those facts; the latter | deem thu con mon
sense and scientific method OF procedure.
humanity" and thu application of this genius
Is often sadly wanted. Now, what are the
facts and phenomena as observed in the X X
NINE? In tho first place. two dissimilar
quartzite underlying, and the limestone SUI
~perinposed: tho limestone, mar the quartz-
lite. is altered and metamorphssed, carrying
caves ana beailiig ores OF various kinds; as
the mine Is al present opened, We find on tn >
nortberly line Il smooth, hard limestone, and
upon that clay, varying in thickness from q
few inches to a foot or more: this apparent
hanging wall has been passed through but in
n Single Elace, and no orc was found in the
vicinity of that wall to the north; within the
limits defined by tn cay seam and quartzite,
the oIe up, to the present time has always
bsen found; the method or occurrence OF this
olo quito NuIieus sOUeLInt5 IL Is IOuDu on
hanging wall, sometimes running through in
teryening space, but more generally on the
foot wall. Tbs bodies Of ore between these
limits have u general dip to the south and
east; in one place the orc extends quite
across from the quartzite to the clay. What
would be the common sense view, assuming
the correctness of the ABOVE facts? 1t
seems to me We mig bit denominate this a Vein
having ore shutes or chimneys, reaching up
wards towards the surface from unknown
depths. The theory Of the deposition of ore
In Limestone countries, a. generally accepted,
is that heated vapors from an internal
source have been forced upward toward the
surface, and have eaten out or dissolved the
car Donate Of lime. The car Donate of lime, as
is well known, Is solu bic in water, containing
free carbonic acid, and, being dissolved, is
borne or percolates away, leaving eavss
which are subsequently fll,d with metallic
mineral; where the dissvlving action has
been greatest openings have formed. and
into these tho metallic minerals would be
forced or drawn up, and there deposited.
Now, applying hese theoretical considera-
| lions to the Facts of the case, we find a series
Of caves of a%.greater or lesser extent extend
ing IN ti mine from a point a short distance
from tn surface to the 9Th or last level. An
other curious phenomenon observa bic at the
far eastern end of the 9th level, at a depth OF
nearly 600 #. from the surface, and 500 or 600
it. east of shat, we find openings in the limo
stone through which the wind draws in-
wardly or presses outwardly; this | take to be
an indication, or next 10 positive proof of an
other set of caves further east, in and near
which 0 experience teaches us to look for a sec
ond chimney of ore; so much for the occurrence
OF ore between these defined limits. The
limestone between these chimneys of ore is
quite variable in character, sometimes very
hard, having doubtless bcen metamorphosed
by silicious yapor or silica carried in solution
in warm water; again, it is broken up or ir-
regular, and at other times soft and sandy;
the nearer we approach the ore chimney the
softor does it become, and more colored or
impregnated with oxide of iron. Another
curious occurrence of the ore, ole
only 10 so large an extent to this mine, is a
mass OF nearly pure quartz ~ to 80 tt wide,
lying almost in the center of the vein or
c%haanel.. This quartz ore contains little or no
lead. AID varies in value IRON S25 to S65 in
gold and silver, and is u sed for f1ux. The oc-
currence OF this nearly pure quartz Is. as
take it, a fact conirmatory of the theory
tn 1t the metamorphism of the irnstone is
due to vapors bearing silica, and at this point
they have been very strong; the oros ar Gu =
Donate, arseniates, and other salts OF LEAD.
intcrspersod among large masses of oxids f
iron; there /. also found, galena, sulphates #
lead. moly b }ate Of lead, arsonieal chloride
of lead, and some others. carrying more
or less of gold and silver. In view of
this act, which explorations have developed,
L am irre,istibly led 20 the couclu-
sion that this is a vein. We have de
fined limits within which the ore i
found; we find evidence of internal
action, and on the walls evidence of
movement, and al clay; these clays
may be denominated the s-lvages OF
the vein; the width of the vein, or ore
channel, as far as the mine is opened,
is quite uniform from $50 to $50 It,,
thus fulfilling all practical requisites
for d~enOminating it vein. The quartz
lte, or foot walls, is disclosed on h
I'd level several hundred ieet, and Il
considerable distance OH Sd, 4th, 9th
and 9th levels; on TWO levels at least
200 IT. and upwards; on the OH level
there is a throw or break of the foot
wall, making about northeast from
where it turns and takes its regular
course; this is the only prominent IT.
regularity in the X X mine. There oc-
ours a curious norIh aud south cross
break in the channel itself; this cross
break is found west of the 2d level,
and running nearly north and south;
ore "a found upon it for a distance of
a few feet north of shaft and south Of
the foot wall; the cross-break extended
above the I'd level only a few feet; the
ore was found against this crosS-break
north of the shaft, extended upward,
waved over the top of it, run 10 a
narrow point and gave out; this was
the only point in the mine where any
of the ore ran north and south. Look
upon. it as merely n local course; the
face 81 this break is quite hard and
very nearly forms a right line with the
general course of both the hanging aud
DOT walls; in other words, defines the
direction of the dip; it is exposed on
the Sd level to a greater extent than
any other level of the mine, viz: First,
on a cross. cut, and again further east;
the face of the wall is exposed a dis
tanee Of $50 feet; the clay is from
a few inches to twenty inches
thick in places; winze follows
wall down IA distance of So feet;
same wall is found in 4lh level, equal
ly we'll defined and opened along the
4th level distance of $50 It,; its dip
is 80 degrees north, and course 10 do
erees south of east and north OF west;
its general Ourse is east and west and
to the north. Next to the X X, on the
north west, is the Eureka Consolida-
ted Company's mine; the workings
of that company ale on the same vein
in my opinion. The mines of the
Eureka Consolidated are either upon,
or TO the north of a body of quartzite;
the Tennyson and Savage are almost
entirely on the quar,zite; the ore was