also discusses several collateral questions, which we have not space

to notice.

There are three papers on Post-pliocene Geology, namely:— 1. On the Formation of Lake-basins in New Zealand, by Mr. W. T. Locke-Travers.

2. On the Occurrence of dead Littoral Shells in the Bed of the German Ocean, forty miles from the coast of Aberdeen, by Mr. Robert Dawson.

3. On the Glacial Phenomena of Caithness, by Mr. T. F. Jamieson.

The third paper is by far the most important, as in it Mr. Jamieson shows that the glacial phenomena of Caithness differ remarkably from those observed in the midland region of Scotland, especially in the direction of the glacial markings, which point with great persistence from N.W. to S.E., or thereabouts; that is to say, from the open sea towards the interior instead of vice versa. The author is therefore of opinion that the glaciation of the Caithness rocks has been produced by a movement of ice from an external region to the north-west; and from the abundance of marine shells in the drift it is probable that it was accumulated by the agency of marine ice. In these respects the traces of glacial action present a very strong contrast to those observed in central Scotland, as will be seen by a reference to former Chronicles.

The distinction is further borne out by the absence from Caithness of tranquilly deposited glacial-marine beds, of valley gravel, and of moraines and gravel hillocks. The area over which these peculiarities extend has not yet been determined, nor has the relative age of the shell-bearing boulder-clay; but it is probable that this is more recent than the true boulder-clay of central Scotland.

Mr. Locke-Travers's paper is occupied with a statement of facts tending to show that Dr. Haast's views of the formation of the New Zealand lake-basins are not borne out by actual phenomena; and Mr. Dawson's note is a record of the remarkable fact stated in the title.

The last paper in the Journal, entitled "On the Carboniferous Slate (or Devonian Rocks) and the Old Red Sandstone of South Ireland and North Devon," by Mr. J. B. Jukes, is of extreme interest to British geologists from its containing a new interpretation of the rocks of Devonshire; we must therefore devote the rest of this Chronicle to its consideration.

Geologists have hitherto considered that the strata of North Devon belong to the "Devonian Rocks," or marine equivalent of the Old Red Sandstone, and that in proceeding from Lynton to Barnstaple successively higher portions of the series were reached, there being a conformable dip southwards for the whole of the distance. In the south-west of Ireland there is a different set of

rocks from what have hitherto been supposed to exist in North Devon. There a formation known as the Carboniferous Slate occurs, reposing conformably on the Old Red Sandstone, and itself as conformably overlain by Coal-measures. In some districts Carboniferous Limestone occurs above the Carboniferous Slate, but then the latter is much thinner than when the former is absent; and, generally, when one of these two formations is most developed the other is either entirely absent or very thin, so that a general section may be drawn, having at one end Carboniferous Slate reposing on Old Red Sandstone, at the other Carboniferous Limestone on the same base, and in the centre a thinner development of both Carboniferous Limestone and Carboniferous Slate, the latter (being the lower rock) reposing as before on Old Red Sandstone.

Now, in this paper Mr. Jukes endeavours to show that the Devonian rocks of North Devon are the same, stratigraphically and lithologically, as the Carboniferous Slate of the south-west of Ireland; and that, instead of there being a conformable and uninterrupted succession of rocks from Lynton to Barnstaple, the series is repeated, owing either to a reversed anticlinal, or (what he thinks more probable) a great east and west fault running through the centre of North Devon, and having a downthrow to the north. At any rate, he considers that the rocks of Baggy and Marwood are the same as those of Lynton, and he suggests the only two possible modes of explaining the circumstance, seeing that the dip of the beds is, to all appearance, persistently south.

THE condition of British mining is far from promising. The continued low prices of copper and tin press very heavily upon our mines, which are now, in nearly all cases, worked to great depths, and necessarily at heavy costs. The wages of the miners in Cornwall and Devonshire are reduced, and as there is but little prospect of improvement for some time to come, emigration is taking place to an unusual degree. This is much to be regretted, as the ablest men are those who emigrate, and we can ill afford to lose this class of labourers. The Mineral Statistics' recently published put us in possession of the results of our mining operations during 1865. Out of 619 mines which have been recently in activity in Cornwall and Devonshire, we find that 238 have suspended operations, and we learn that several others, and unfortunately some of those mines employing the largest numbers of people, are to be closed shortly.

The premonitions conveyed by these unfortunate results cast a gloom over all mining operations; but, unfortunately, those interested in the mines cannot be persuaded to adopt the only step by which they may mitigate the evil under which they groan. At present the supply of tin and copper ores is beyond the requirements of the smelters, and therefore they purchase only at the lowest prices. These prices are not renumerative, consequently nearly all the mines are now working at a loss. Yet they struggle on, because the managers and the mines would be thrown upon the cold mercies of the world if the works were abandoned. Thus, our tin mines, especially, are producing far more tin than is wanted, and a glutted market necessarily compels low prices. This state of things cannot long continue: slowly, reluctantly, one mine after another is suspended, and real distress is staring a most industrious population in the face. Our young and able miners are emigrating; our older men suffer without murmuring, and hope for better days. (Since the above was written there has been an advance in the price of tin ore to the extent of 77. 10s. the ton, and a small advance upon copper. The natural result of this is to induce a more cheerful spirit. It is also satisfactory to note that the miners instead of emigrating are now seeking and finding employment in the colliery and other districts.)

The quantity of tin ore raised in 1865 was 15,686 tons, from which 10,039 tons of metallic tin were obtained; within the same period we imported, principally from the Dutch settlements in the Eastern Archipelago, 5,699 tons of tin and 639 tons of tin ore and regulus.

There were 203 copper mines in the United Kingdom sending copper ore to market during 1865. These produced 198,298 tons of ore, from which were smelted 11,888 tons of copper of the value of 1,134,6447. It appears, however, from a table given in the Mineral Statistics,' that the price at which the ore sells, and the produce of the ores raised, have for many years steadily declined. There has been, for some considerable time, no important discovery of any new deposits of copper, we may therefore infer that copper mining in these islands has seen its best days. Our importations of copper in 1865 were very large. From our Colonies and Foreign parts we received 82,562 tons of copper ore, 39,686 tons of copper regulus, and 7,026 tons of copper in bricks and pigs. If we were to draw our conclusions from the statements given of the public sales of copper ores, we should naturally say that the imports were steadily declining. The Foreign and Colonial ores sold in 1856 being 28,997 tons, against 16,332 sold in 1865, but it must not be forgotten that 66,230 tons of copper ore passed into the hands of the smelters by private contract purchases. This is, in many respects, an unfortunate state of things; the only benefit

arising from this system, to balance numerous disadvantages, being to establish more securely the monopoly of the copper smelters.

The British isles produced of lead ore 90,452 tons, the value of which was 1,153,1547.; from this was obtained 67,181 tons of lead and 724,856 ounces of silver, the value of the lead being 1,433,1617., and that of the silver being 199,3357.

Passing from silver to gold, we find that the Welsh mountains produced in 1865 1,664 ounces and 11 dwts. of gold. It would be interesting to know at what cost this gold was obtained. Of zine ores we appear to have produced 17,842 tons, and of iron pyrites (sulphur ores) 114,195 tons.

By far the most important of our mineral products remain to be noticed. Our coal and our iron must, at present-view them in whatever light we may-be regarded as the mainstays of our manufactures and of our commerce. In 1865 we had 3,256 collieries at work, and from them we drew the enormous quantity of 98,150,587 tons, of this we exported 9,170,477 tons, retaining 88,980,110 for home consumption. Of this it appears that 14,457,762 tons were used in making 4,819,254 tons of pig iron, and 14,325,390 tons employed in converting this into merchant iron. Our purpose in this place is merely to chronicle facts as they arise; we could have commented on the appointment of the Royal Commission to inquire into the duration of our coal fields, and other matters connected with this subject, had they not been treated fully in another division of our Journal.*

It may be incidentally stated that we learn the labours of the Royal Commission have been divided amongst several committees, who are to consider:

1. The waste of coal in getting.

2. The waste of coal in consumption.

3. The depth to which collieries may be worked and ventilated. 4. The existence of coal under the Eastern Counties.

5. The statistics of produce-trade and manufacture.

The extension of our coal fields being committed to the charge of the Geological Survey.

The total value of our mineral productions is thus given in the 'Mineral Statistics':

Total value of Minerals, 32,359,1057.

The total value of the Metals obtained from the metalliferous ores of the United Kingdom being

The value of the Coal raised

Earthy Minerals, not including CLAY OF BUILD

ING STONES

£15,773,287

24,537,646

1,434,496

£41,745,429

* "Our Coal Resources and our Prosperity," Art. I.

being the money-worth of the productions drawn from our rocks. To this must now be added the mineral oils produced in this country from the bituminous shales and cannel coal. The value of those mineral oils has not been given by Mr. R. Hunt, but we have every reason for believing that it does not fall short of three millions sterling. If therefore to the above we add this and the estimated value of our clays, bricks, slates, and building stones, we cannot estimate the mineral wealth of the United Kingdom at the present time at less than fifty millions sterling.

The necessity of working our collieries with economy is forcing -more and more-upon the attention of our coal proprietors the application of machinery for cutting coal. We have already described several of those machines; some of which are, we believe, doing their work effectively. We cannot afford space in this Journal for any long descriptions of machines, howsoever ingenious they may be, which have not received the test of a sufficiently long experience in actual working, to determine their merits.

Our attention has been called to a new hydraulic coal-cutting machine manufactured by Messrs. Carrett, Marshall, and Co., of Leeds. The machine is described as automatic, of three-horse power, and cutting at the rate of fifteen yards per hour, four feet into or under the coal, and at any height or angle, and at once going over. It uses in this work thirty gallons of water, making fifteen strokes a minute at a pressure of about 300 lbs., the cutting tools displacing only three inches of the coal so undercut. There are doubtless many advantages in the use of hydraulic power rather than that of air. In one case the power can be conveyed without loss; in the other the loss of force is great. This machine was highly spoken of at the recent Meeting of the British Association.

Messrs. Pigott and Farrar, of Barnsley, are said to have made some great improvements in a machine for pumping or compressing air for working coal-cutting machines, or for propelling engines of any kind used in a colliery. We also hear of a new coal-cutting machine, the joint invention of Mr. Gillett, mechanical engineer, and Mr. E. Beecher, the colliery engineer at the Thorncliff and Chapeltown Collieries. When these machines have had a sufficient trial we may again return to a consideration of them.

MINERALOGY.

M. Pisani having received a black Spinelle from Haute-Loire, through the attention of M. Bertrand de Lorn, has submitted it to careful examination, and communicated the results to the Academy of Sciences of Paris, through M. Ste. Claire-Deville. This black Spinelle has been found principally in the Haute-Loire, but it has been met with in Cantal and the Puy-de-Dome. It is found in the