Imatges de pàgina

of Ailsa ; it also forms part of the island of Arran, and the lofty Cullin mountains in the island of Skye.

Porphyry.--I observed fragments of porphyry among the granite mountains in the island of Arran, which is probably of primitive formation; and the porphyry, which forms so considerable a part of the hill of Glamoscard in Skye, seems to be of primitive formation.

. Primitive Limestone, or Marble.-This rock occurs in vertical strata at I-columb-kill, also in the island of Tirie, and in several parts of the mainland. I observed it alternating with primary rocks, particularly at Portsoy, where it is in vertical strata, and alternates with talcaceous shistus and serpentine.

Primitive Greenstone. I have not met with this rock in any part of Scotland excepting in the island of Islay, yet I think it very pro. bable that a careful examination may discover it in many places.

Serpentine. There are no strata of this rock in the Hebrides, nor the Orkney islands ; but in Shetland it forms extensive hills, and there it seems evidently to be of primitive formation. At the interesting spot, Portsoy, there are great vertical strata of serpentine alternating with marble, talcaceous, and hornblende shistus.

' Quartz.-In the islands of Isla and Jura there are mountains of granular quartz, and it is there to be observed alternating with and passing into micaceous shistus. In the isle of Coll there are also considerable rocks of granular quartz. In the island of Tirie I obberved the rare appearance of a vein of granular quartz traversing strata of micaceous shistus and hornblende slate. In Caithness the mountain of Scaraban is composed of quartz; and at Portsoy there is a hill which affords shistose quartz. In many places veins of quartz are to be observed traversing the primary strata, and in the island of Bute there is a quartz vein which presents appearances irreconcileable with the Plutonic theory.

Pitchstone.—The only species of this stone which I have ever seen, that may be considered as primary, is that upon the hill of Glamoscard in the island of Skye. It there seems to alternate with porphyry, but of this I am not yet certain. In the island of Arran there are appearances of pitchstone in the form of veins traversing the granite ; but as all veins are of an after-formation to the rocks which they traverse, this cannot be reckoned equally old with the granite, or other primitive rocks.

• Transition Rocks (Uebergangsgeburge). Grawacken.--This is a rare rock in the districts through which I passed. The only appearance I ever noticed was a small portion lying on ardesia in the island of Seil.

Greenstone. - The greenstone of the island of Mull appears to belong to this formation, as it is found near to limestone that contains belemnites.

· Limestone. This species is found in the island of Mull, and contains in it cornu Ammonis and belemnites; hence I reckon it to belong to the transition rocks.

! STRATIFIED Rocks (Flotzgeburge). Sandstone.—of this I observed two kinds, the siliceous and are gillaceous.

The siliceous does not frequently occur. The sandstone of the island of Rume `approaches nearly to this kind ; and in the Orkney islands there are strata of siliceous sandstone that alternate with argillaceous sandstone. Argillaceous sandstone forms the Cumbray islands, the south extremities of Bute and Arran ; and it also appears in the islands of Seil, Múll, Eigg, Skye, Rasay, and Scalpa. Almost the whole of the Orkney islands are composed of argillaceous sandstone ; but it forms a very small portion of the Shetland islands. It also skirts the east coast of Scotland, from the Pentland Frith to the small fishing-town called Buckie ; and again this sand. stone makes its appearance near to Aberdeen, and continues along the shore all the way to the Frith of Forth.

Limestone. - In the island of Arran there are considerable strata of limestone, which is covered by argillaceous sandstone; and in some places the limestone and sandstone alternate. In the Orkneys lime. stone is to be observed covered by sandstone, and even traversed by veins of sandstone.

Argillite with numerous shells is found in the island of Arran, and in the island of Eigg.

Basalt.-This rock, which, as we have before observed, is pecu. liar to the flotzgeburge, is found in almost every part of Scotland, either in strata or in veins. I observed it disposed in strata in the island of Seil, at Oban, in the islands of Mull, Eigg, Canna, and Skye ; and these strata either alternate with argillaceous sandstone, wacken, or greenstone. Frequently also veins of basalt traverse these strata.

Basalt Veins. These veins are extremely common in most of the Hebrides, but are rarely to be observed in the Shetland or Orkney islands. I observed them traversing granite, gneiss, micaceous sbistus, sienite, porphyry, hornblende slate, sandstone, and limestone. In the island of Arran there are several very remarkable veins which are partly formed of basalt. Thus in Glencloy there is a vein, (traversing clay porphyry), which is composed of basalt in the middle, but upon one side is sandstone breccia, and on the other is hard siliceous sandstone. At Tormore, upon the west side of the island of Arran, there are several other very remarkable veins partly formed of basalt.

Basalt Tuff.-I observed this rock at Dumbarton castle, and in the islands of Mull and Canna, where it always accompanies rocks of trap formation. In the island of Canna it is remarkable for having pieces of wood inclosed.

Pitchstone.—This curious fossil is found very frequently in the island of Arran, but generally in the form of veins." These veins traverse the common argillaceous sandstone, and are often of great magnitude. It is also disposed in stratified veins along with other substances at Tormore in Arran. In the island of Mull it seems to lie between sandstone and basalt ; but in Eigg it forms considerable

veins traversing basalt. This fossil, which was before considered as very rare, is thus shown not to be so uncommon; and I have lately learned that it has been observed in veins traversing sandstone in Mor. ven, and in veins traversing basalt at Ardnamurchan.

Greenstone. --The country between the primary strata at Dunkeld, and the banks of the Frith of Forth, presents many appearances of flotz greenstone; and in the same tract there is also wacken of a similar formation,

Coal.-In the island of Arran there is a stratum of blind coal inclosed in sandstone. In Mull, Eigg, Canna, Skye, it is observed always stratified with basalt or wacken.

VOLCANIC Rocks * have never been discovered in Scotland. • ALLUVIAL. — Of these there are examples in the Highland valleys, where the débris from the mountains are deposited in beds and covered by heath. The great banks of sand, and the immense beds of peat which we find sometimes alternating with beds of clay or sand, are of this kind.' Vol. i. P. xviii.

The account of Arran the author before published with his Shetland Islands; and it here, by the help of very loose printing, occupies half the first volume ! We refer our readers to our account of Mr. Jameson's former publication (Vol. 28, p. 24, New Arr.). Werner is not a man of classical learning; and his syenite is erroneously taken from Pliny, with whom it merely and solely implies red granite. We know not whence our au. thor has taken the unclassical term shistus, instead of schistus, whose very essence and sound he thus destroys.

The mineralogy of Arran is followed by that of Bute, Isla (Ilay), Jura, and Mull. Our author did not visit Staffa, and has not even seen the exterior western chain from Lewis to Bernera! Hence we may judge of the fitness of the general title of the book which has been thus hastily obtruded upon the public, as if the author were impatient to communicate his great discoveries!

As our readers will not be so sanguine in their admiration, we shall content ourselves with extracting the short account of two little isles, and return to the second volume at some future opportunity.

• SEIL.–This island, about three miles long, and two miles broad, is separated from the island of Easdale by a strait a few hundred feet broad, and from the mainland by a narrow pass, over which a bridge has been thrown. The island is in general flat, yet not without hills, from the highest of which we have a pleasant view of the many small isles scattered over the ocean, with the distant moun. tains of Mull and Jura.

• The greater part of the island is composed of rocks of primitive

5* Of the pseudo-volcanic rocks, which are different species of rocks that have been exposed to accidental fire, we have instances in Fifeshire. Upon the shore between Dysart and Easter Weinyss I picked up several fine specimens of porcellanite, which seems to be the clay that accompanies the coal allered by sirc, as masses of scoria and charcoal still adhered to it,'

formation, and these are micaceous shistus and ardesia. Basaltic veins are also very frequent, traversing both kinds of strata ; and, where the stratificd matter is washed away, or has fallen down by decomposition, the perpendicular veins appear often like basaltic craigs, and, at first sight, may be taken for strata. Considerable veins of quartz are also to be observed traversing the primary strata upon the south and east shores of the island; and, near to the southern extremity, I observed a vein of quartz which contained a quantity of iron pyrites, but apparently too small to be of any im. portance. * Besides these primary strata, I observed, upon several parts of the island, small portions of the transition (uebergangsgeburge) and flotz rocks (Alotzgeburge). Near to Mr. Campbell's house I observed the ardesia covered by grauwacken, and both apparently traversed with the same basalt vein, which leads us to suppose that they were formed at the same time ; and, in support of this, I may mention, that German mineralogists have observed these rocks to alternate. Upon the side of the island opposite to Easdale, we have an appearance of flotz strata. Immediately upon the shore, I observed red-coloured argillaceous sandstone, stratified with sandstone breccia and basalt, and the whole traversed with basaltic veins. There are also quarries of ardesia tegularis in some parts of the island. But the principal attention of the proprietors is turned to the island of Easdale, where the slate has hitherto been found in great quantity. °• EASDALE.-This island is about half a mile long, and of the same breadth, and is celebrated for its having afforded the best and greatest quantity of ardesia tegularis of any part of equal extent in Great Britain. A very considerable portion of the island is composed of ardesia tegularis, and this is traversed by basalt veins. The ardesia, where in contact with the basalt, is useless, being shivery, and breaking into small pieces, unfit for the making of slates : it is also equally bad where veins of quartz or limestone occur.

• The island is now cut very low, excepting a small portion at the south end ; and levels have been made out to the sea, to carry off the rain water. As the greater part of the island is now upon a level with the sea, it is plain that the raising of slates must be abandonea, or continue to be worked, at a considerable expense, by means of machinery; which would probably be a bad plan, when we consider the extent and excellence of the rival quarries at Ballyhulish. The most judicious arrangement would certainly be, to open more extensive quarries in the neighbouring isles of Luing and Seil, where, in all probability, after the ground is properly cleared, good slates may be found.

• The ardesia in this island was first quarried about one hundred years ago, but was for a long time of litele importance, as sandstone flag and tiles were generally used for roofing houses. As the use of slates became more prevalent, the quarries were enlarged ; and the present managers having obtained a very favorable lease, these quarries have been wrought to so great an extent, that 5,000,000 slates are annually shipped from this island. The number of workmen is at present about 300; and they are divided into quar. riers and day-labourers. The quarriers are paid annually at a certain rate for every thousand slates : from rod. to 15d. I believe, as their work has been attended with more or less difficulty. The day-labourers are employed at the company's expense in opening new quare ries, and have from rod. to Is. a day. Vol. i. P. 192.

Art. II.-Allwood's Literary Antiquities of Greece. (Continued

. : from p. 23.) W E have already observed that Mr. Allwood derives the names of all the Grecian deities, heroes, and chiefs, from the Ammonian radicals of Mr. Bryant; or elements which, in the opinion of this latter scholar, were in common use among the descendents of Chus the son of Ham; many of which may be supposed to have constituted a part of the primitive vocabulary of man anterior to the partition of lands, or the confusion of tongues at Babel; and the greater part of which referred to the idolatrous rites cultivated among that ingenious but reprobate people, upon the introduction of the worship of the sun, the ark, and the serpent. The adoration of the sun he supposes to have commenced first of all; shortly afterwards that of the ark, as the wonderful vessel in whose capacious womb a remnant of man and beast were preserved on the bosom of the mighty deep, while every animal around them was doomed to utter destruction; or as a type of Noah himself the great progenitor of mankind, and the inspiration he displayed in the construction of such a machine, and the prediction of such a deluge ;-to which two sources of idolatry speedily succeeded the worship of the serpent; who, from the coruscation of his scales, and more especially when curled up in the figure of a circle, was an apt emblem of the sun, or of the surrounding care and protection of the supreme Deity himself. Thus far we have no objection: we will admit that the sun might have been termed among the Babylonians Ur, Or, or On; that Noah might have been indiscriminately denominated Noë, Naus, Xuth, or Thoth; that the vessel he constructed may have been equally styled erech, men, bout or but, bar, hip or theb; and that the name for the serpent was Ob or Oub. We feel no difficulty in deriving the names and worship of many of the Grecian gods and heroes from these and other elements of the same kind; but much is nevertheless highly questionable---scarcely plausible enough to establish a probability; and we can by no means allow of the de. duction contended for by Mr. Bryant, and now advanced in many respects to a still greater extent by Mr. Allwood, that the names of all the earlier heroes, legislators, and chiefs of Egypt and Greece, are allegorical, and their histories entirely fabulous,

« AnteriorContinua »