The Express.
London, England, 1862-10-08 00:00:00

Szorios O._—GEOLOGY,

Dr. T. 4rxeuriii;iirmide TrssMnunicatiou " On the
Origin NM Mode dt Otioinesse el the Petroleum of Werth
America." He said It wee aapomd that these one had
aornethleg to do with coal, and they were therefore celled
coal oils ; but the rocks from which they came were far
below any coal-bearing strata. He believed that they were
formed in the particular beds in which they were found, and
not by heat, but by some slow and peculiar decomposition
of an organic animal or vegetable matter at the ordinary
temperature of the atmosphere or earth's crust
Professor ANSTED said this was a very important subject
for investigation, as these oil-produoiog rocks extended
over • larger tract of country than Europe, vie., from
Canada to the Mississippi. These rocks yielded an enor-
mous quantity of oil. but it was found that the supply
from a vele( gradually diminished, and he believed it
would ultimately be exhausted and be followed probably
by water. He did not think that Dr. Hunt had cleared
up the question u to the origin of petroleum.
Dr. Hula admitted he had left the question in • vague
state, as it was one on which chemistry must mainly throw
light.
Professor HARILIIIBIS, F.R.S., said that neer Liverpool
there was a large deposit of peat, lying under sand, which
was bring gradually converted into petroleum. The oil
floated on the surface, and becoming consolidated formed a
kind of pitch.
Dr. Hew read another paper, "On the Structure and
Origin of attain Limestones and Dolomites."

GOLD MINING IN WALES.
Mr. T. A. KAADWILI FAIR, read • paper "On the
gold-bearing strata of Merionethshire." MU said that at
Manchester last year he read • paper before the geological
section to show the probability of gold seeking in the Dot.
golly district being at no very renimai date of commercial
value. In order to teat the accuracy of his former experi-
ments he had employed for several months past in • labor&
tory on the mountains en eminent analytical chemist, whose
asmaya he would now give. The rocks were of the Cam-
brian and Lower Silurian series, forming • junction
in • very sinuous course, and cut througie very
frequently by narrow banks of iporphyritic greenstone.
The metalliferous veins had • general bearing N.E. sad
S.W., with an underlie to the north, the strata dipping
generally south. One mine had in it 20 strong metalliferous
lodes. One very remarkable junction of about 14 lodes was
40 feet wide, and the whole of this masa of lode stuff con-
tained more car less gold. A large number of assays he re-
cently had made gave from 3 to 19 dwts. of gold to the ton
of quarts. Picked specimens gave as much as 16 ounces to
the ton, and more than 700 ounces of gold was taken from
about OO tons of minerals from all parts of the mine. He
then gave descriptions of various other mines with their
yields of gold, and said that by the nee of proper machinery
there could be no doubt whatever of an average of 8 or 10
dwts. of gold to the ton paying a large profit, and thus
opening a branch of industry of vast importance to the
country. Mr. Reedwin exhibited • bar of gold weighing 37
ounces obtained from the quartz in one of the mines, and
several articles of jewellery made from pure Merionethshire
gold.
Professor ANSTZD said the existence of gold in this country
was well known to the Romans and to the native islanders
before then. They both obtained large quantities of pre-
I doss metal in their
day, and in Ireland abo the Ramona
I had found gold. We had therefore,onoe had our "diggings"
as well as the peopled Australia and New Zealand, but it
War only within the last two yam that an interest in the
gold mines of Wales had been revived by the discovery of
remarkable veins containing large quantities of gold.
Professor Ileocwicx said that Humboldt's theory was
that all gold-bearing veins ran north and south, and the
vain in question did not appear to deviate far from that
direction ; lint although that theory had bean adapted by
Sir Roderick Murchison and other authorities, he looked
upon it as a rash attempt at generalisation upon insufficient
fade- He, however, did not repudiate the opinion ex-
prinesd by Humboldt ; he only said that it iovolsedanon
question to which attention might well be directed. Two
other opinions of Humboldt be also combatted at their
Manchester moieties. via, that gold- bearing veins were
productive only near the surface, and that gold
itself was IS very modern production of the earth.
I He believed that gold was an old production, because it was
found in old rocks, and the fact of large nuggets being ob-
tained near the surface could easily be explained by the
enormous dilapidation of the auriferous mountains by me-
chanical maim, and the intim of water driving down the
material into hollows and streams.
_ . .

A gentlemm;TromL;traliasaid that in that colony the
■old reefs ran north and south, but there were small spurs
from them running due east and west which were sometimes
richer in gold than the main reefs. He also stated that at
Ballarat gold had been obtained at a depth of 630 feet, sad
to Moo amount of 5 os. to atm: of quark..
Profeseor ANSTED mid that the veins mentioned by Hr.
Readwia ran rather north-seat and south-west. With regard
to the direction of lode. of gold mines gloomily, he thought
It followed a good deal the elevation of the country. It was
an interesting, important, and entirely new fact, that geld
woo newfound at ► depth of fathoms in rich quantities,
because it had been the prevalent opinion among geologists
that gold diminished in quantity as they went downwards.
This discovery would very much extend the working of
mines.

Soma other mere were rood, but thoy were not al so im-
portant a motors ea the above.