asserting that there was nothing in the characters of the substance itself, or in the minerals associated with it, as found in Saxony, which stamps it as the product of fire; and he might be excused, considering the vague descriptions of geological phænomena given by travellers at the time he commenced his career, in framing a system without reference to their statements; but he cannot be so well exculpated for his obstinacy in adhering to the same erroneous conclusions in spite of the evidence afterwards brought together in contradiction to them, and that even by some of the most eminent of his own disciples, such as Humboldt and Von Buch, who seem to have deviated more and more widely from the creed of their master in proportion as their acquaintance with volcanic phænomena became more extended.

If we follow into Lusatia the chain of the mountains of Saxony, we find that many of the eminences are capped with basalt, presenting there the same characters and relations as it does in Saxony*. The only difference to be observed is, that in the latter country the basaltic hills are situated near the summit of the mountain ridge, whereas in Lusatia they are placed nearer to its foot. One of the most considerable indeed, the Lanscrone, near Gærlitz, a conical hill near 1000 feet in height, stands entirely isolated in the plain, and at a distance of about six miles from the mountain-chain.

In the Riesengebirge of Silesia, which may be considered a sort of prolongation of the Saxon chain, the hill, called the Kleine Schneegrebe, is on its north-west side composed of basalt, which appears to have been protruded through the midst of the granite forming the remainder of the hillt. In one part huge fragments of this rock are entangled in, and cemented into a compact mass by, a basaltic paste, the whole forming a singular species of conglomerate. The basalt is amygdaloidal, and contains zeolite and mesotype. It attains to the height of 4661 feet above the sea.

Von Buch, in his description of the environs of Landeck in

See Daubuisson on Basalt, English translation, p. 73. + Singer in Leonhard's Taschenbuch, 1823; and for the Wernerian view of its formation, Daubuisson on Basalt, p. 235, English translation. Professor Jameson is there said to regard it as an "upfilling,” that is, he considers its position as dependent upon the irregularity of the granitic surface in that part.

the county of Glatz*, has noticed four basaltic hills superimposed on primitive rocks, the most considerable of which is the mountain of Deberschaar.

It also appears from the late work of Eynhausen on the Geology of Upper Silesia, that a numerous series of isolated basaltic cones extends from the Oder at Fachenburg to Troppau, and from thence to Freudenthal in Moravia t.

A few miles south of the latter place, but north of Olmutz, is the little town of Hof, near which, in the chain of hills called Gesenke, occurs a volcanic mass which exhibits indications of a more recent origin.

The following account of it is extracted from a German periodical work called the “Hesperus’ for January 1821.

The hill called the Raudenberg, which is situated to the south-east of the village of that name, is 2250 feet above the sea, and composed, together with basalt, of reddish, greyish,

* Min. Description of the environs of Landeck by Von Buch, translated by Dr. Anderson. Edinburgh, 1810.

+ The following are a few of the details given by the author quoted in the text.

Between Michelau and Falkenburg basalt crops out of alluvial soil.

Between Troppelwitz and Jagerndorf are the basaltic cones of Schönweise; near Troppau those of Stremplowitz and Ottendorf; both amongst transition slate and greywacke.

The basalt of Kohlenberg lies amongst primitive şlate.

Basalt also occurs between Tillowitz and Schiedlow, south of Falkenberg, and near Raklo.

Basalt blocks are found near Lipten.

At Annaberg is a basaltic cone 1300 or 1400 feet high, the loftiest emi. nence in the district.

A basaltic hill called the Mulwitzberg extends between the towns of Michelau and Falkenberg; the basalt is prismatic, contains little olivine, but much steatite. On the sides are blocks of a quartzy sandstone, perhaps tertiary.

Near Schönweise, not far from Jagerndorf, are two cones of basalt, surrounded by slate-clay, passing into transition conglomerate.

South of Troppau, at Ottendorf, basalt is met with in a transition country. North-west of ditto, at Stremplowitz, are cones of basalt partly porous.

Between Bennesch and Raudenberg, is basaltic tufa containing augite, constituting a building-stone much like the lava of Andernach.

At Kohlerberg, south of Freudenthal, occurs a basaltic amygdaloid, containing quartz, calcareous spar, chalcedony and chlorite. It resembles the basalt of the Buchberg near Landshut, and is the nearest point to the primary range at which basalt is found.

or blackish scoriæ, which look as fresh as those of the Puy de la Nugère, or of Vesuvius.

These products inclose fragments of granitic rocks, and of mica or clay-slate, which are much altered, and seem to pass into the scoriform mass enveloping them. To the south-east of this hill, near Heydenpiltsch, are two hillocks of compact basalt; more to the south, near Brochersdorf, is a basaltic hill called the Saunikal; and on the right of the Mora river, near Friedland, are two others. To the north-east are two funnel-shaped cavities, of which the largest is seventy-five feet in breadth and eighteen in depth.

These basalts rise from the midst of mica-slate, are compact and sometimes columnar, and contain olivine.

Lastly, on the western border of Moravia, near the frontier of Hungary, is a small igneous formation near Banow, described by Dr. Boué in the geological memoir on Germany above noticed.

He represents it as a cone of grey clinkstone, containing crystals of hornblende, and having the few pores distributed through its substance elongated in a vertical direction. On its western side it incloses portions of hardened clay and sandstone of various colours, and on its eastern side it has thrown up and cracked in various directions a very large mass of the same kinds of rock, which have also become indurated where in contact with it.

Thus it would appear, that on either side of the great primary chain which passes through the centre of Germany, the several parts of which are known under the names of the Thuringerwald, the Fichtelgebirge, the Erzgebirge, the Riesengebirge, &c., there occurs a line of basaltic cones, which, though detached one from the other, are so placed as to indicate a certain mutual connexion. This notion respecting them is confirmed by observing that similar formations occur chiefly at a certain distance from these primary ranges, for Von Hoff has remarked *, that if one line be drawn from Upper Lusatia to Kulmbach in the country of Bayreuth, and another from the same point in a north-westerly direction, so as to pass through the towns of Eisenach and Munden, no

• See De la Beche's Geological Memoirs, p. 100.

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basaltic rock is to be met with north of that line, notwithstanding the abundant occurrence of it to the south.

The same author has further shown in another of his publications* that the shocks of earthquakes are most common, in the same direction as that of the basaltic masses themselves, and round a certain distance on either side of the line in which they occur.

The importance of these observations will be more clearly perceived, when it has been shown that rocks indisputably volcanic are placed in the same linear direction, as it will add one to the series of proofs by which the origin of trap rocks is connected with that of modern lavas.

* Geschichte der Veranderungen der Erdoberflache, vol. ii., an excellent work, which has led me to refer to several writings, in the German language especially, that might otherwise have escaped my notice.

CHAPTER V.

VOLCANIC ROCKS OF HUNGARY.

Volcanic rocks of Hungary.-General description of the country.–Five va

rieties of the Trachytic formation found in it-l. Trachyte, properly so called—2. Trachytic Porphyry—3. Pearlstone—4. Millstone Trachyte5. Pumiceous Conglomeratc-re-united-rendered aluminous.—Theory of the formation of Alum.-Other minerals found in the Trachyte.Synopsis of the Genus Trachyte.-Analogous formations in other countries and in Hungary itself, such as Felspar Porphyry.—Basaltic rocks

in Hungary. One of the most remarkable countries in Europe for the scale in which volcanic operations have taken place, the more so indeed because it lies at a great distance from the sea, and therefore, as we shall find, in a position the most opposite to that which recent volcanos usually affect, is Hungary, which consists of two vast plains, the one about forty leagues in length and twenty-five in breadth, including that part of Western Hungary which is bounded by the Austrian mountains on the west, the Carpathians on the north, and the Bakony on the south-east; the other about 120 leagues long and eighty broad, forming Lower Hungary, and bounded by the Danube and by the immense marshes which lie on the east of the Theiss at the foot of the mountains of Transylvania. The alluvial character of both these plains, and their low level, which does not exceed 140 or 170 feet above that of the ocean, render it easy to imagine that they have both at a former period been occupied by water, forming two extensive inland seas or lakes, of which that of Balaton, Neusiedel and others are the remains.

The mountain-chain which bounds the most northern of these plains, and separates Hungary from Gallicia, is composed in a great degree of primary mountains, rising in some places to the height of more than 7000 feet. They consist of granite, gneiss, mica-slate, clay-slate and felspathic porphyry, with which are associated certain hornblende rocks regarded