Chap. XIX.] 
GOLD IN BEITAIN. 
451 
egg-, none of these superficial accumulations have been considered worthy of 
continuous exploration. 
In Scotland, whilst slender traces only of gold have been detected in the 
older crystalline rocks of the Northern Highlands *, albeit many of them are 
now known to be of Lower-Silurian age, the metal was formerly found in the 
slates of the South of Scotland (Lead Hills), which, like those alluded to in 
.North and South Wales, are also of that age. These South-Scottish gold-mines, 
after having, in the reign of James the Fifth, afforded a small sum, were 
abandoned as soon as the cost of production exceeded the value of the ore ex- 
tracted f . They occurred in a region where the strata have been much pene- 
trated by porphyries and other igneous rocks. 
In Ireland we read the same lesson. It is from the altered Lower Silurian 
schists of Wicklow, which clasp around the eruptive granite of Croghan-Kin- 
shela, and are traversed by hornblendic greenstones, that gold was derived ; and 
fragments of it, detached from the sides of that mountain and washed down 
by the rivulets, continue to be still picked up by the natives %. 
Now, if any portion of these old slaty British rocks, or their associated erup- 
tive masses, had been largely penetrated by gold, then most assuredly much 
more auriferous debris would have been recognized in the local adjacent gravel 
— just as it occurs in all really gold-bearing lands. But as no rich auriferous 
sand or gravel is known in any part of the British Isles, we may rest satisfied 
that in our own country, as in many others, the quantity of gold originally im- 
parted to the Silurian or other rocks was small, and has, for profitable working, 
been exhausted, with the exception of the mines north of Dolgelly §. 
Even in Bohemia, which produced so much gold in the Middle Ages, and 
where the Silurian strata are, as we have seen (Chap. XV.), penetrated by many 
igneous rocks (and in parts much metamorphosed), there are now no gold-works, 
though other ores (copper &c.) are profitably extracted ; and, just as in the 
rocky and mountainous tracts of Britain, very few places only can be cited 
which have been auriferous. The Thiiringerwald, and some chains of Central 
Germany, also anciently afforded a little gold in rare and widely separated loca- 
lities || ; but these regions, as well as the Peninsula and its ' golden Tagus,' 
* Near Loch Erne Head, a metalliferous vein- 11, 1865. 
stone observed by the late Marquis of Breadal- § The reader who has attended to this sub- 
bane was found to be slightly impregnated with ject will observe that the chief argument I have 
gold. The gold occurred in a gossan, contiguous employed in other writings (see note, p. 448) to 
to the junction of trap with crystalline limestone satisfy the public mind that auriferous sites in 
and schists (probably of Lower- Silurian age), and the old countries of Europe would for the most 
is associated with arsenical pyrites and lead-ore. part prove slightly profitable only, was that all 
t See Harkness on the ' Lower Silurian Rocks such works had ceased in former times for want 
of Scotland,' Quart. Journ. Greol.Soc.vol.viii.p.396. of remuneration. Let me, however, say that, 
I The Earl of Wicklow, whose property is in whilst I believe the old gold-tracts of Europe 
the vicinity of the mountain of Croghan-Kinshela, have, on the whole, been exhausted of their 
has collected several ' pepitas ' of this Irish gold, wealth, there may still be found spots where a 
the largest being about two inches long. They are little profit is attainable. I would further guard 
free from quartz or other rocky matrix, and have any inferences I have drawn from our previous 
been picked out of the de"bris or coarse gravel on state of knowledge, by saying that my opinions 
that slope of the hill where a rivulet descends were formed irrespective of the new inventions in 
through the property of the Earl of Carysfort. mechanical science. Crushing-machines and the 
£To veinstone in situ has ever been detected (Mills improved application of mercury may, indeed, 
and Weaver, Trans. Dublin Society, and Weaver, liberate a notable quantity of ore from a matrix of 
Trans. Greol. Soc. Lond. 2nd ser. vol. i.) ; and al- apparently slight value, and thus set at nought 
though poor persons have stealthily procured the experience of ages. Not pretending to enter 
specimens during this century, the quantity has into this mercantile part of the question, I adhere, 
never been sufficient to lead to the belief that however, to the belief expressed throughout the 
really productive diggings could be opened at the text, that gold will mainly be found in the old 
Royal G-old-mine of Croghan. Tinstone is said rocks indicated, and will, on the whole, be worked 
to have been found with the gold here, as in Corn- to the greatest advantage, as during past ages, in 
wall and other places (Fitton, Trans. Greol. Soc. the natural debris of those rocks. 
Lond., vol. i. p. 270) : the phenomena are well || The sands of the River Rhine (which drains 
described by Professor W. W. Smyth, Records of so vast a rocky region) are in one part slightly 
the School of Mines, vol. i. p. 3, with a map; auriferous; but the cost of extraction of the gold 
see also Proc. Roy. Greol. Soc. Ireland, January has been too great to repay the speculators. 
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