he skips over the only actual coal formations known in the county. He prefents us with no account of the ftrata in which the working coal is included, the thicknefs of the feams, their inclination, or bearing. All we can gather from his description, and from the figure annexed, is, that these beds affume the extraordinary form of concave cups; and, without the flighteft fhadow of proof, they are faid to rest upon his tranfition rocks.' In p. 89, he mentions a columnar glance coal,'* a little above Crawick-bridge,' which is to be obferved paffing into the graphite, but not fo diftinctly as near Cumnock in Ayrshire, where there is a graphite mine." In his elaborate defcription of this wonderful phenomenon, we fee nothing but what is very common in Scotland, where a dike or vein interfects the coal ftratum. In fuch cafes the coal is often found, to a confiderable extent from the vein, reduced to a powder refembling graphite; and even where it remains folid, it is deprived of its bitumen. When this occurs, the miners fay the coal is foul, or that it is difeafed: and from the change of quality in the ftratum, they often know they are approaching a dike, long before the coal ceafes to be folid. From his defcription, the unwary reader may be led to conclude that the whole ftratum confifted either of graphite, or of columnar glance coal. But the fact is, that the ftratum is the common splint coal, inclining to the caking Newcastle coal. Near the dike, the ftratum approaches to plumbago. At a greater diftance, a few fcattered columns appear, without any uniformity, surrounded by a brittle crumbling coal, of the fame quality. This coal, when heated to redness, emits neither flame nor smoke, and remains long unconfumed, though it does not poffefs the characteristic properties of good blind coal. It is, in fact, what colliers call foul or dif enfed coal. At the distance of fome fathoms, the coal becomes, in the collier's phrafe, perfectly clean; that is, a bituminous, bright burning, and caking coal. The level of the coal on the other fide of the dike is depreffed about twelve fathoms. We have seen inftances where the correfponding ftrata met on each fide of a dike, at nearly the fame horizontal level; and in fuch cafes, little or no difeafe in the ftrata could be observed. But where the ftrata are much elevated or depreffed, there is generally a confiderable extent of disease in the part, which is either thrown greatly up or down. In p. io, he characterifes all the coal in Dumfries-fhire, by the * Our author formerly ufed the term glance lead, because it was Englih. In a note, p. 78, he explains the glance coal by the German appellation, coal blende. Could he not have called it blind coal, and then the people of Dumfries-fhire would have understood his meaning. the general name of flate coal, though it breaks with equal faciJity in all directions, and is intermediate between the fplint coal of the Lothians and the caking coal of Newcastle. The cannel coal of Auchintaggart, near Sanquhar, is the only fpecies known to us, which can be called flate or fchiftic coal, because it divides into thin plates. Having made thefe remarks on the very imperfect account he gives of the actual or exifting coal formations, we fhall proceed to the confideration of his independent, or rather ideal coal formations. The only coal fields at prefent known in the county, are at Sanquhar in Nithfdale, and at Cannoby on the Esk. Our author, however, makes a great part of the county an independent coal formation, and is anxious to prove that the reddish brown freeflone, which abounds in the county, covers coal, or that coal may be found under it. So intent is he upon his independent coal formations, that he never stops to inform us of a notorious fact, that no fuch freeftone is known to exift in any of the coal fields that have yet been discovered. In p. 81, after a careful examination,' he decides, without the smallest proof, that the red fandftone of Dumfries is not of the fame formation with what he is pleafed to call the old red fanditone of Cumberland,' and that the former belongs to the independent coal formation.' In fupport of his argument, he has recourfe to Mid-Lothian, and points out the following places where red fandstone is afferted by him to exift in coal fields. 1. In Dryden water, near Loanhead. 2. Near the paper-mills on the Eik, continuing to Hathornden and Roflin. 3. At Collington. 4. At Craigmillar. 5. At Salisbury Craigs. Our author is perpetually embarrafling this queftion by the authority of Werner, and other eminent German mineralogifts. In p. 80. and 81., he reprefents Werner as fhewing fome of their opinions to be falfe, and that the independent coal formation does not lye under the old red fandtone formation.' But from what he ftates immediately after, it would feem that Werner thinks coal may be found under fome newer red fanditone formations. We with our author had fpecified the marks by which we might diftinguish between thefe valuable new formations, and the unproductive old ones. Thefe Germans may have reprefented facts as they occurred in their own country; but as this is a queftion, in the decifion of which, authority ought to have no influence, we hope to prove, by a reference to facts, that coal no where exifts under red fandstone in this country, whether it be of new or old formation. We must premife, that it requires an eye accustomed to obferve thefe materials, to diftinguish the red or reddish brown fand stone, ftone, which we deem very unfavourable to coal, from other fandftones, which are not unfavourable. We do not efteem a reddish yellow, or yellowish brown unfavourable, but the cortrary; though thefe may be incautiously mistaken for the unfavourable fandftone. One difcriminating mark of the latter is, that parts of a bed, or even entire beds, are interfperfed with fmall rounded pebbles, and conftitute that species of breccia, or puddingstone, to which our author afligns the name of amygda loid. Other entire beds are compofed of this, or of a coarfer breccia. Now, though we would be understood to speak with confiderable diffidence, we must state, that, as far as our experience extends, we never knew, or heard of, a fingle example of amygdaloid or breccia occurring in the ftrata that covered coal. We must farther remark, that the unfavourable fandítone often alternates with white fandstone, inclining to yellow, of a very fine grain, and well adapted for elegant architecture; but a fingle bed of genuine red, or reddish brown sandstone, interpofed between thefe ftrata, appears to us highly unpropitious, if not fatal to coal, as far as that group of ftrata extends. Having offered thefe explanatory obfervations, let us now at tend to our author's proof of the existence of coal under the red fandftone of Dumfries, derived from the red fandftone of Mid-Lothian. From the parish of Borthwick, an irregular belt, or zone, of red fandtone, croffes part of the parish of Cairnton, and the parish of Lafwade, between Roflin and the paper-mills. Its progrefs is nearly from fouth to north; and its eaftern boundary is feen to run pretty regularly, until it interfects part of Craigmillar on the eaft; it then paffes onward until it is loft fomewhere near Portobello. Its western boundary runs along from Roflin, until it is intercepted by the eastern bafe of the Pentland Hills, and is loft, or covered, by the whinftone rocks projected from that bafe. From Portobello, this fanditone takes an irregular weftern courfe. It includes the Calton Hill, the ridge on which the old town of Edinburgh is built; and here the North Loch is the boundary between the red fandftone and the coal metals. From the fouthern bafe of Edinburgh caftle, the red fandftone occupies all the fpace between the north fide of the Pent land Hills, and an irregular line drawn from this point, in a direction of weft by fouth, nearly to Mid-Calder. In this tract there are fome large inroads of the coal metais into the red fandstone, and feveral projections of the red fandftone into the coal metals: but a line eaft of the river Calder seems to form the boundary of the coal metals, from a little way above the town, to the weftern point of the Pentland Hills. The bafaltic rocks rocks of Corstorphine Hill are feen, in fome points, to rest upon the coal metals. But, farther towards the weft, a range of red sandstone is seen to interfect part of the parishes of Corftorphine and Kirklifton, which terminates near Queensferry weftward, and comes down to the fea eastward of the Hawes. Whether this be a detached range, or an arm projected from the former, we fhall not pretend to determine; though the latter feems most probable. The latter alfo projects another arm, weftward, from Kirklifton through the county of Linlithgow, to the town of Linlithgow itself, and through part of Stirlingshire. Our author, p. 167, afferts that Craigmillar belongs to the coal formation, though it does not exhibit the most distant fymptom of coal. Southward from Craigmillar, the red fandítone and the coal metals are frequently feen to meet, and to dip in oppofite directions; and though coal is wrought on each fide of the red fandstone which forms this zone, no particle of it was ever found in the red fandftone itfelf. Where the ftrata stand. at fo high an angle, and are cut fo deeply by the North and South Efks, furely if there had been any coal in the red fandstone in question, it must have been expofed to view. The red fandftone mentioned at Loanhead is part of another range, which occupies the rifing grounds for a great way towards the fouth. Though it has coal in its immediate neighbourhood, no particie of coal was ever found in the red fandítone itself. In the fame page, our author afferts, that Salisbury Craigs belongs to the coal formation;' of which there is not the moft diftant fymptom, though the ftrata are expofed to the depth of feveral hundred feet. The flate clay' he mentions in this rock, is commonly of a red colour; and the sandstone is mostly red, except the ftrata next the whinstone, and a few others. 6 From Salisbury Craigs and Craigmillar, this fandstone stretches through Canaan towards Collington. It occupies Bruntisfield links, and forms the bafis of the ridge on which the old town of Edinburgh is built; as was lately made manifeft by digging the foundation for the new bank buildings. At the North Loch, the coalmetals again appear; and the New Town is built on ftrata from which coal was formerly wrought. All the tract of country betwixt this part and the fea, having Portobello on the east, and an irregular line paffing Almond Water, above Cramond Bridge, on the weft, is founded on coal-metals. In p. 166, our author fays, that immediately behind the manfe of Collington, there is a beautiful fection of the coalfield.' Thefe trata are of a reddish brown colour;' but though they are almoft perpendicular, and are cut to a very great depth, did our author, or any other perfon, ever find coal in them? The greyifh black-coloured flate-clay,' does not occur behind the manfe of Collington, but farther down, towards the Lanark road, where the coal metals again appear; and here the fandftone is not red or brown, being either white, or grey, or blue, or yellowish. We may remark, that when dark-coloured clay fchiftus occurs in red fandftone, which very rarely happens, it commonly writes white, like roof flate. But the darkcoloured fchiftus in coal fields, as it owes its colour to carbon and bitumen, commonly draws lines of its own colour, or nearly approaching to it. In p. 108. io9. we are prefented with an argument, which, fhould all our author has faid about the coal formations of MidLothian, fail in producing its effect, he thinks fufficient to force conviction on the moft obftinate fceptic. In lower Silefia, the coal formation is composed of thick ftrata of reddish brown fandstone. Strengthened by this argument, with much confidence, he concludes with a truifm which no one will difpute, that the coal-fields of Mid-Lothian and Dumfries-fhire, belong to the independent coal formation.' But as, under the term coal-fields, he evidently includes fields of red fandstone, we shall endeavour to prove, that coal does not occur in fuch fields, in any part of Scotland that is known to us. What may be the cafe in Silefia, we fhall not pretend to decide; but as this gentleman has confounded the red fandstone of Mid-Lothian, which, though often contiguous, is never found to cover coal, with the other fpecies below which coal is actually found, we cannot help fufpecting he may have committed the fame mistake with regard to the fandstone of Silefia. In the county of Lanark, a broad belt of red fandftone runs northward from the parish of Kilbride. It occupies most of the parifh of Blantyre, and part of the parishes of Cambuslang and Hamilton. Crolling the Clyde, it runs a long way through the parish of Bothwell, and throws out feveral arms. Though coal is wrought along the boundary of this fandstone, on each fide, no particle of coal was ever found included in it. The diftrict of Cunningham, in Ayrshire, is moftly compofed of red fandstone: but, from Saltcoats to Irvine, there is a narrow tract of coaft, in which there is vaft abundance of coal, and the fandftone is fuch as ufually covers coal. The boundary between these two species of fandftone, is marked with almost mathematical precifion; and is ufually diftinguished by an oppofition in the dip or inclination of the ftrata. In the red fandftone, no veftige of coal ever was observed. We might mention several other places in the counties of Lanark, Renfrew, and Ayr where the coal-metals and coal come into immediate contact with red fandstone, without the latter containing a fingle par ticle |