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Torquay, in South Devon. It would seem that this identification has not been considered perfectly reliable, since the fossil has not found a place in subsequent works on the Devonshire beds, or in Professor Morris's Catalogue of British Fossils.

The mineral and mechanical characters of the Old Red rocks may, perhaps, sufficiently explain the absence in them of mollusks and other dwellers at the seabottom; but there seems no satisfactory mode of accounting for the non-appearance of fishes in the slates and limestones of Devon and Cornwall. We are asked, by one proposed solution of the problem, to suppose that some geographical difficulty or barrier separated the two areas and prevented the migration and mingling of their inhabitants; whilst another suggests that the Old Red fish were probably at home in fresh water only, and ought not to be looked for in beds so decidedly marine as those of Devon and Cornwall.

The interesting and important discovery, by Sir R. I. Murchison*, of the intermixture, in the same Devonian bed in Russia, of the fish of the Upper and Middle Old Red of Scotland with the shells of Devonshire seems to dispose of the latter of the two proposed solutions just mentioned, but leaves the difficulty untouched; nor does it appear that the synchronism of the representative beds in Britain neces sarily flows from it. It proves, of course, that the fish and shells lived at one and the same time in Russian, not that they did so in British, waters. We may have an example here of the distinction between geological contemporaneity and synchrony, so ably pointed out, on a recent occasion, by Professor Huxley †.

At the Meeting of the British Association held at Cork, in 1843, Mr. Peach brought under the notice of the Geological Section certain fossils which had then recently been found, by Mr. Couch, in the Devonian slates of Polperro, in Cornwall. The paleontologists to whom they were then submitted considered them to be the remains of fishes; this was the opinion also of the late Mr. Hugh Miller at first, but subsequently he considered them to be very doubtful and extremely puzzling; ultimately they were pronounced, by Professor M'Coy and Mr. Carter, of Cambridge, to be sponges merely. It may still be doubted, however, whether certain fossils found with them were not true ichthyolites; indeed, one specimen which, a few years since, I found in the same beds at Looe, in Cornwall, has been pronounced by Sir P. Egerton and others to be a decided ichthyodorulitet. It has not been identified, however, even generically.

A few weeks since, I had the good fortune to find a fossil in the Pleurodictyum slates at Meadfoot, near Torquay; that is, in certainly the lowest group of the rocks of South Devon, and which Sir R. I. Murchison has placed on the horizon of the Cephalaspidian and Pteraspidian beds-the lowest of his divisions of the Old Red of Scotland. The fossil was at once identified by Mr. Davies, of the British Museum, as a scale, or rather a portion of one, of Phyllolepis concentricus, Agass.—a fish known only by its fossil scales, which have hitherto been found only in the Clashbinnie beds, belonging to Sir R. I. Murchison's "Upper Old Red."

This fossil, then, appears to necessitate the belief, either that the organism which it represents had a greater vertical range than has been supposed (that is, that it belonged to the Lower and Middle, as well as Upper, Old Red fauna), or that the Pleurodictyum beds of Devon and Cornwall, instead of being on the horizon of the Lower, are on that of the Upper Old Red Series of Scotland.

To accept the first of these (apparently the only two) alternatives would be to accept the difficulty of supposing that Phyllolepis dates from the times of Cephalaspis, the extinction of which it witnessed, as well as the subsequent introduction and withdrawal of Coccosteus, Asterolepis, and others; and yet that, unlike its early contemporaries, it failed to leave any trace of its existence in the Old Red rocks, save only in the uppermost of their three groups.

Rejecting this, however, we seem compelled to adopt its rival, which amounts to this:-There are in Devon and Cornwall no representatives of the Lower and Middle Old Red rocks of Scotland, but the Lowest (the Pleurodictyum) beds of the former are on the horizon of the upper division of the latter, an opinion in

*Siluria, 3rd edition, p. 382.

+Anniversary Address, Quart. Journ. Geol. Soc. vol. xvii. p. 40, &c.
See 'Geologist,' vol. iv. pl. 6, p. 346.

harmony with those of Sir H. De la Beche and the Rev. David Williams, already spoken of, as well as that advocated by myself in an earlier paper*. It will be seen also that the indications of the supposed scale found by Professor Phillips were to the same effect. Like the Old Red Sandstone fish found in Russia by Sir R. I. Murchison, the Phyllolepis-scale was surrounded with marine shells†, and also by corals; hence the ancient fish to which it belonged was not incapable of living in the sea.

On the Gold-bearing Strata of Merionethshire.
By T. A. READWIN, F.G.S., F.S.S.

The author referred to a paper read before the Association at Manchester in 1861, the object of which, he said, was to point out the probability of gold-seeking in the Dolgelley district being, at no very remote date, of commercial importance. He stated that, since the last Meeting, he had acquired additional facts connected with the subject, and his wish was to present them in support of the opinion expressed in the paper referred to.

The author said that he had employed an eminent analytical chemist for several months upon the spot, to test the accuracy of his former experiments; and the assays referred to in the paper were made of 8000 grains, taken from quantities of 56 lbs., after the most careful sampling, instead of the customary 400 grains.

He said that the geological features of the district were now too well known to require more than a repetition of the general statement that the rocks are of the Cambrian and Lower Silurian series, forming a junction in a very sinuous course, and frequently cut through by narrow bands of porphyritic greenstone.

The metalliferous veins have a general bearing N.E. and S. W., with an underlie to the north.

The auriferous district under notice is comprised in the Ordnance Survey Maps, 75, S.E., and the upper part of 59, N.E.

For convenience, he divides the district into the following sections:-Cwmheisian, Maesgwm, Berthwllyd, Cambrian, Clogau, and Vigra.

The parishes included in the notice are Llanfachreth, Trawsfynydd, Llanddwye, Llaneltyd, and Llanaber.

THE CWMHEISIAN SECTION.

The Cumheisian uchaf Mine has in it more than twenty strong metalliferous lodes. One very remarkable junction of about fourteen lodes is 40 feet wide, and the whole of this mass of lode-stuff contains more or less gold.

A large number of assays gave from 3 to 19 dwts. of gold to the ton of quartz. Picked specimens of galena have given as much as 16 ounces to the ton; and more than 170 ounces of gold were taken by Mr. Clement from about 300 tons of mineral from all parts of the mine. Mr. Arthur Dean produced 148 ounces from 157 tons of ore. Gold, visible in blendic quartz, has been discovered within the last

month.

Cumheisian Isaf is a silver-lead mine, adjoining the last-mentioned on the south. The galena yields about 47 ounces of silver to the ton; and one lode in the mine gives, on assay, 5 to 11 dwts. of gold to the ton of mineral.

Gwynfynydd Mine is opposite Cwmheisian Ucha, on the west bank of the river Mawddach. Galena from this mine, though poor in silver, has occasionally given as much as 8 ounces of gold to the ton.

Hafod-y-bach Mine.-Samples of quartz, indiscriminately taken from this mine, from 3 to 5 dwts. of gold to the ton. The mineral here is probably richer than this.

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Tyddynglwadis Silver-Lead Mine is on the west bank of the river Mawddach, about eight miles from Dolgelley, in the direction of Tanybwlch. This mine is situate exactly at the junction of the Cambrian and Lower Silurian rocks, which is distinctly observable at the top of the charming waterfall, Pistil-y-Cain.

The average quantity of silver contained in the galena is from 50 to 60 ounces to

Report of the British Association, 1860, p. 100.

+ Siluria, 3rd edition, pp. 383 and 433.

the ton. Selected specimens have given as much as 300 ounces. Visible gold is occasionally found in the galena, and he had seen it also in copper-pyrites.

Assays for gold gave from 6 to 11 dwts. per ton. Some moss pulled from the river-side had small specks of gold attached to the roots.

Penmaen Copper Mine has some very strong metalliferous veins upon it, said to be auriferous. Visible gold is said to have been found here.

Dolfrwynog Gold Mine is situate about a mile over the mountain eastward from Cwmheisian, and includes the farms denoted on the Ordnance Map-Dolfrwynog, Tynsimna, Bwlchroswen, and Rhoswen. This is a very remarkable property. There are several strong lodes, only one of which he notices in the paper: it is known as the "Gold Lode." He had stones of beautiful quartz from this lode, containing at least 400 ounces of gold to the ton!; and he believes that a goodly amount of gold will be obtained from this lode, although it underlies north 6 feet in a fathom, and at the depth of about 60 fathoms enters a spur of the North Dolfrwynog Mine. He had specimens from this lode in the International Exhibition, and had seen stones taken from a depth of nearly 40 fathoms, richer than any at Clogau. The bulk of this lode-stuff will give on an average, he thought, from 10 to 15 dwts. of gold to the ton.

East Dolfrwynog Mine is on the east of the last-mentioned, and takes in the farms marked on the Ordnance Map-Buarthrae, Doledd, and Penbryn. There are six or more lodes on this property, which give on assay from 6 to 9 dwts. of gold to the ton.

The Dolfrwynog Gold Lode runs into Penbryn-a few yards from the spot, at Dolfrwynog, where the richest gold was discovered. It is about 5 feet wide, and of precisely the same character, and will probably prove as rich.

North Dolfrwynog Gold and Copper Mine is situate on the east bank of the Mawddach. There are ten metalliferous veins in this property, and all of them auriferous. The Dolfrwynog rich Gold Lode underlies into this sett; and it is certain that at the depth of 60 fathoms very rich gold will be found.

Assays of the lode-stuff from this mine give an average of 9 dwts. of gold to the

ton.

The author said that he had once extracted as much as 6 ounces to the ton from stuff in which gold was not detectable under a powerful microscope. He had recently superintended the removal of about 100 tons of alluvium from the eastern bank of the Mawddach, with the object of discovering whether the particles of gold found therein increased in size from the surface to the bed-rock. He found this to be the case; and the sample of coarse-grain gold produced was perhaps the most interesting item of the recent discoveries. This gold was obtained by a very rough washing over a trough 30 feet long,—a process which washed away all the fine gold, weighing probably ten times as much as the coarse gold obtained. It is probable that the whole side of this mountain will be found to contain gold in paying quantities on the erection of machinery to economize labour.

West Dolfrwynog Copper and Gold Mine adjoins the last-mentioned on the south, and is marked on the Ordnance Map the "Turf Copper Mine," from the singular fact that, some time ago, about £10,000 of copper was sold from the ashes of peat, there burnt for the purpose. The water at the present time is highly saturated with copper; and a shaft, now in course of sinking, will probably discover a large deposit of copper-ore, if not gold.

The lode-stuff of this mine gives on assay about the same quantity of gold as North Dolfrwynog. On a portion of the mine the author found the alluvium to contain gold under the same circumstances and in about the same proportions as the North Dolfrwynog Mine. Gold has been obtained here at the rate of 6 ounces to the ton. The minerals of this mine and Dolfiwynog are identical in character.

THE MAESGWM SECTION

Is on the western side of the Trawsfynydd Road, nearly opposite Tyddynglwadis. Maesgum Mining Sett extends over 1600 acres, and has three large lodes on it, which are all auriferous.

The Cwmheisian Great Gold Lode runs into it, and the Ganllwyd Gold Lode.

Ganllwyd Gold Mine has two very distinct lodes, from one of which he had taken several stones of visible gold. The poorest stuff contains on assay 10 to 11 dwts. of gold to the ton. This mine will probably prove a second Clogau, as the lodestuff is identical in character with the Saint David's Lode.

Coed-cy-fair Mine is S.W. of Maesgwm, and has the same surface appearance. Visible gold has recently been found here. Assays have given 3 to 5 dwts. to the ton from surface quartz.

THE BERTHWLLYD SECTION.

Berthellyd Mine is situate on the summit of the precipitous and lofty ridge of hills to the west of the curious little roadside inn, the "Oakley Arms," at Tyn-ygroes, on the Trawsfynydd road from Dolgelley.

There is what Mr. Warington Smyth appropriately calls "that grand champion lode Berthwllyd," which runs in a direction N.N.E. and S.S.W. for about a mile. Blende and galena are the chief products of this mine, all of which are auriferous. Only a few days ago, the author saw both blende and galena pounded fine, and gold washed therefrom, in the proportion of 3 to 4 ounces to the ton. He himself washed gold from the alluvium of so fine a quality that it floated on water.

As much as 6 ounces to the ton has recently been extracted by Britten's amalgamating-machine. This mine is destined to produce, he thinks, from its inexhaustible supply of metalliferous quartz, some extraordinary results.

Goitref Mine adjoins the last, the quartzose lodes of which are auriferous. Caegwernog Mine adjoins Berthwllyd, and is favoured with a continuation of the Great Champion Lode at Berthwllyd. Trials of ores from this mine have produced sometimes as much as 8 ounces to the ton. A few days ago, the author visited the spot for the first time, and discovered an old heap of calcined stuff upon which were visible globules of gold. Assays of the surface lode-stuff produced from 2 to 4 dwts. to the ton.

Cae Maur Mine adjoins the Berthwllyd and Caegwernog Mines. It was here that the first gold was discovered. Visible gold has recently been found. Assays give from 9 to 11 dwts. to the ton of surface mineral.

Gold is also found in the alluvium, by washing, in about the same proportions as at North and West Dolfrwynog.

Benrhos Mine.-The alluvium here contains specks of gold, similar to the lastmentioned.

Tyny-benrhos Mine adjoins the last, and contains gold in the alluvium, as above. Glasdir Copper Mine, to the N.E. of Tyny-benrhos, is a very remarkable property; £15,000 worth of copper-ore has been sold from this place, simply the result of quarrying. Very rich gold-stones have been found here, some of which the author had seen.

THE CAMBRIAN SECTION.

This section extends along the north side of the turnpike-road from Dolgelley to Barmouth.

The Cambrian Gold Mine has six remarkable blende lodes, three of which the author knows to be highly auriferous. No. 6 lode produces gold occasionally very rich in blende. He had himself extracted gold from the blende-ore, at the rate of 300 ounces to the ton. There can be no question about gold being found here in paying quantities. Very rich ore has been recently raised. One large specimen contained gold in the slate. A very rich specimen was exhibited.

The Cumabseifian (East Clogau) Mine is situate to the north of the Cambrian Mine. The noticeable lode in this sett is one that has the appearance of being a continuation of the Saint David's Lode at Clogau. The quartz is similar, and contains gold on assay. Mr. Clement's analysis gives 18 dwts. 14 grs. to the ton.

The Princess Alice Mine, situate between the Cambrian and the Prince of Wales Mines, has given gold on assay at the rate of 8 dwts. to the ton. The lode-stuff has the same character as the Cambrian. The author extracted gold from it in 1856.

Moel Ispri Mine, on the N.E. of the last, has yielded, it is said, at the rate of 8 ounces of gold to the ton of galena.

The Prince of Wales Mine is on the east of the Princess Alice. It has several

remarkable galena and blende lodes. Some specimens from this mine in the author's case at the International Exhibition contain from 300 to 400 ounces of gold to the ton. The lode-stuff will probably yield as much on the average as the Saint David's Lode at Clogau. Seventeen ounces of gold were recently obtained from 5 cwt. of blende ore. A very rich specimen was exhibited.

THE CLOGAU SECTION.

The now celebrated Clogau Gold Mine is situate about a mile and a half north of the "Halfway House," on the turnpike-road from Dolgelley to Barmouth, the most charming road in Europe.

This property contains a large number of lodes, mineralized throughout more or less with galena, blende, and copper-pyrites, and with the occasional occurrence of bismuth and tellurium.

The Saint David's Gold Lode is the most noted, in consequence of its having outstripped all other gold-mines of the kingdom by doing the last thing that was predicted of it, namely "pay a profit." Of this, however, there can be but little doubt, as, by official returns up to the 30th September last, 7892 ounces of gold have been sold to the Bank of England, the produce of only 1091 tons of quartz!— 1173 ounces of which were produced from 1072 tons of mineral in which the gold was not visible, and the astonishing quantity of 67183 ounces from only 18 tons 17 cwt. 3 qrs. 14 lbs. of quartz, realizing nearly £30,000, at a cost of some £3000, or less! No quartz-mining on record has given such a result. This remarkable lode produces gold in quartz, in the 15-fathom level, at the rate of an ounce to the

ton.

The author stated that, in his paper of last year, he had placed on record the product of the first hundredweight of Welsh gold. He had now to record more than four hundredweight; and he believed the mine, under proper management, to be capable of producing far greater results than those just mentioned.

A bar of gold weighing 37 ounces, part of the produce alluded to, was exhibited, and a chain of pure gold, manufactured by Messrs. Watherston and Brogden. The first three quarters of the year 1862 show the following result:

[blocks in formation]

-which is equal to 18 dwts. 13 grs. per ton from the former, and 330 ozs. 9 dwts. from the latter, or an average of 6 ozs. 12 dwts. per ton from both. The gold brought £3 178. per ounce, after deducting expenses for realizing same; nett, £20,390 158. 5d.

The Garthgell Mine is situate between the Cambrian and Clogau Mines, and receives the lodes of both mines. The Cambrian Gold Lode runs into the sett a few yards from the spot where visible gold is now being raised, and the Saint David's Gold Lode has been traced on the Clogau side up to the boundary of the Garthgell Sett. The same results as the Cambrian are expected daily. The ores by assay give from 2 to 10 dwts. of gold to the ton at surface, and, to appearance, increase in depth. A shallow adit will cut the Cambrian Gold Lode at about the same level as that company's present working.

Tynycornel Farm, on the west of Clogau, has the Saint David's Lode running through it. This is at present unexplored; but as the lode on each side of the farm is auriferous, it is more than probable that gold will be found here also.

Hendreforian Mine lies in the middle of the Hirgwm valley, between the Vigra and Clogau Mountains. Gold has been produced here by assay. The indications here are good.

West Clogau Mine, at Llachfraith, has yielded from a ton of quartz 17 dwts. of fine gold-about half, probably, of what it contained, when the means used to extract it are considered. The author found gold visible in the quartz here in 1856, at nearly 150 fathoms lower than the upper level at Saint David's Gold Lode.

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