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and in the south-east of the great mountain chain, the naphtha-springs and naphtha-fire of Baku and the Caspian peninsula, Apscheron. The magnitude and connection of this phenomenon was, however, first discovered by Abich, distinguished by his profound knowledge of this part of Asia. According to him, the mud-volcanoes and naphthafires of the Caucasus are arranged in a distinctly recognisable manner in certain lines, which stand in unmistakeable relation with the axes of elevation and the directions of dislocation of the strata of rock. The greatest space, of nearly 4,000 square miles, is occupied by genetically connected mud-volcanoes, naphtha-emanations and saline springs in the south-eastern part of the Caucacus, in an isosceles triangle, the base of which is the shore of the Casbe derivable from the accidental similarity of sound in the misunderstood name of a mountain. There are better arguments, of which Klausen also mentions one. From the actual association of Typhon and the Caucasus, and from the express testimony of Pherecydes of Syros (in the time of the 58th Olympiad), it is clear that the eastern extremity of the world was regarded as a volcanic mountain. According to one of the Scholia to Apollonius (Scholia in Apoll. Rhod., ed. Schaefferi, 1813, v. 1210, p. 524), Pherecydes says, in the Theogony, "that Typhon, when pursued, fled to the Caucasus, and that then the mountain burnt (or was set on fire); that from thence Typhon fled to Italy, when the island Pithecusa was thrown around (as it were, poured around) him." But Pithecusa is the island Enaria (now Ischia), upon which the Epomeus (Epopon) cast forth fire and lava, according to Julius Obsequens, 95 years before our era, then during the reigns of Titus and Diocletian, and lastly, in the year 1302, according to the statement of Tolomeo Fiadoni of Lucca, who was at that time Prior of Santa Maria Novella. "It is singular," as Boeckh, the profound student of antiquity, writes to me, "that Pherecydes should make Typhon fly from the Caucasus because it burnt, as he himself is the originator of subterraneous fire; but that his residence upon the Caucasus rests upon the occurrence of volcanic eruptions there, appears to me to be undeniable." Apollonius Rhodius (Argon. lib. ii, v. 1212-1217, ed. Beck) in speaking of the birth of the Colchian Dragon, also places in the Caucasus the rock of Typhon, on which the giant was struck by the lightning of Jupiter. Although the lava-streams and crater-lakes of the high land of Kely, the eruptions of Ararat and Elburuz, or the currents of obsidian and pumice-stone from the old craters of the Riotandagh, may be placed in a pre-historic period, still the many hundred flames which even now break forth from fissures in the Caucasus, both from mountains of seven or eight thousand feet in height and from broad plains, may have been a sufficient reason for regarding the entire mountain district of the Caucasus as a Typhonic seat of fire.

VOL. V.

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pian Sea near Balachani (to the north of Baku) and one of the mouths of the Kur (Araxes), near the hot springs of Sallian. The apex of such a triangle is situated near the Schagdagh in the elevated valley of Kinalughi. There, at the boundary of a dolomitic and slate formation, at an elevation of 8350 feet above the Caspian Sea, close to the village of Kinalughi itself, break forth the perpetual fires of the Schagdagh, which have never been extinguished by meteorological occurrences. The central axis of this triangle corresponds with the direction which the earthquakes, so often experienced in Schamacha upon the banks of the Pyrsagat, appear constantly to follow. When the northwestern direction just indicated is traced further, it strikes upon the hot sulphurous springs of Akti, and then becomes the line of strike of the principal crest of the Caucasus where it rises up into the Kasbegk and bounds Daghestan. The salses of the lower region, which are often regularly arranged in series, gradually become more numerous towards the shore of the Caspian, between Sallian, the mouth of the Pyrsagat (near the island of Swinoi), and the peninsula of Apscheron. They present traces of repeated mud eruptions in earlier times, and often bear at their summits small cones, from which combustible and often spontaneously ignited gas is poured forth, and which are exactly similar in form to the hornitos of Jorullo in Mexico. Considerable eruptions of flame were particularly frequent between 1844 and 1849, at the Oudplidagh, Nahalath, and Turandagh. Close to the mouth of the Pyrsagat on the mud volcano Toprachali, "black marly fragments, which at the first glance might be confounded with dense basalt, and extremely fine-grained doleritic rocks" are found (a proof of the exceptional, greatly increased intensity of the subterranean heat). At other points on the peninsula of Apscheron, Lenz found slag-like fragments as products of eruption; and during the great eruption of flame of Backlichli (7th February, 1839), small hollow balls, like the so-called ashes of the true volcanoes, were carried by the wind to a long distance.62

62 Humboldt, Asie Centrale, t. ii, pp. 511 and 513. I have already (t. ii, p. 201) called attention to the fact that Edrisi does not mention the fire of Baku, although it is described diffusely as a Nefala-land, that is to say, rich in burning naphtha springs, by Massudi Cothbeddin, two

In the north-western extremity towards the Cimmerian Bosphorus are the mud volcanoes of the peninsula of Taman, which form one group with those of Aklanisowka and Jenikale near Kertsch. One of the salses of Taman exhibited an eruption of mud and gas on the 27th of February, 1793, in which, after much subterranean noise, a column of fire half enveloped in black smoke (dense aqueous vapour?) rose to a height of several hundred feet. It is a remarkable phenomenon, and instructive as regards the nature of the Volcancitos de Turbaco, that the gas of Taman, which was tested in 1811 by Frederick Parrot and Engelhardt, was not inflammable; whilst the gas collected by Göbel in the same place, 23 years later, burnt, from the mouth of a glass tube, with a bluish flame like all emanations from the salses in the south-eastern Caucasus, but also, when carefully analysed, contained in 100 parts 92.8 of carburetted hydrogen and 5 parts of carbonic oxide gas.

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A phenomenon certainly nearly allied to these in its origin, although different as regards the matter produced, is presented by the eruptions of boracic acid vapours in the Tuscan Maremma, known under the names of lagoni, fummarole, soffioni, and even volcani, near Possara, Castel Novo, and Monte Cerboli. The vapours have an average temperature of 205° to 212°, and according to Pella, in certain points, as much as 347°. They rise in part directly from clefts in the rocks, and partly from stagnant pools, in which they throw up small cones of fluid clay. They are seen to diffuse themselves in the air in whitish eddies. The boracic acid, which is brought up by the aqueous vapours from the bosom of the earth, cannot be obtained when the vapours of the soffioni are condensed in very wide and long tubes, but becomes diffused in the atmosphere in consequence of its volatility. The acid is only procured in the beautiful establishments of Count Larderel, when the orifices of the

hundred years before, in the tenth century (see Frähn, Ibn Fozlan, p. 245, and on the etymology of the Median word naphtha, Asiatic Journal, vol. xiii, p. 124).

63 Compare Moritz von Engelhardt and F. Parrot, Reise in die Krym und den Kaukasus, 1815, Th. i, s. 71, with Göbel, Reise in die Steppen des süd lichen Russlands, 1838, Th. i, s. 249-253, and Th. ii, s. 138 —144.

soffioni are covered directly by the fluid of the basin. According to Payen's excellent analysis, the gaseous emanations contain 0.57 of carbonic acid, 0.35 of nitrogen, and only 0.07 of oxygen, and 0·001 of sulphuric acid. Where the boracic acid vapours permeate the clefts of the rock, they deposit sulphur. According to Sir Roderick Murchi son's investigations the rock is in part of a chalky nature, and in part an eocene formation, containing nummulites-a macigno, which is penetrated by the uncovered and elevated serpentine 65 of the neighbourhood (near Monte Rotondo). In this case, and in the crater of Volcano, asks Bischof, do not hot aqueous vapours act upon and decompose boracic minerals, such as rocks rich in datolithe, axinite or tourmaline? 66

In the variety and grandeur of the phenomena, the system of soffioni in Iceland exceeds anything that we are acquainted with on the continent. Actual mud-springs burst forth in the fumarole-field of Krisuvek and Reykjalidh, from small basins with crater-like margins in a bluish

gray

64 Payen, De l'acide boracique des Suffioni de la Toscane, in the Annales de Chimie et de Physique, 3me série, t. i, 1841, pp. 247-255; Bischof, Chem. und Physik. Geologie, Bd. i, s. 669–691; Etablissements industriels de l'acide boracique en Toscane, by the Count de Larderel, p. 8.

65 Sir Roderick Impey Murchison, On the vents of hot vapour in Tuscany, 1850, p. 7 (see also the earlier geognostic observations of Hoffmann, in Karsten's und Dechen's Archiv für Mineral. Bd. xiii, 1839, s. 19). From old but trustworthy traditions, Targioni Tozzeti asserts that some of these boracic acid springs which are constantly changing their place of eruption were once seen to be luminous (ignited) at night. In order to increase the geological interest of the observations of Murchison and Pareto upon the volcanic relations of the serpentine formation in Italy, I may here advert to the fact that the flame of the Asiatic Chimæra (near the town of Deliktasch, the ancient Phaselis in Lycia, on the west coast of the Gulf of Adalia) which has been burning for several thousand years, also rises from a hill on the slope of the Solimandagh, in which serpentine in position and blocks of limestone have been found. Rather more to the south, on the small island of Grambusa, the limestone is deposited upon dark-coloured serpentine. See the important work of Admiral Beaufort (Survey of the Coasts of Caramania, 1818, pp. 40 and 48), whose statements are confirmed by the specimens of rocks just brought home (May, 1854), by a highly talente l artist, Albrecht Berg (Pierre de Tchihatcheff, Asie Mineure, 1853, t. i, p. 407.)

C6 Bischof, op. cit. s. 682.

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clay. Here also the fissures of the springs may be traced in determinate directions." There is no portion of the earth, where hot springs, salses and gas-eruptions occur, that has been made the subject of such admirable and complete chemical investigations as those on Iceland, which we owe to the acute and persevering exertions of Bunsen. Nowhere, perhaps, in such a great extent of country, or so near the surface, is such a multifarious spectacle of chemical decompositions, conversions, and new formations to be witnessed.

Passing from Iceland to the neighbouring American continent we find in the State of New York, in the neighbourhood of Fredonia, not far from Lake Erie, a multitude of jets of inflammable gas (carburetted hydrogen), breaking forth from fissures in a basin of Devonian sandstone strata, and partly employed for the purpose of illumination. Other springs of inflammable gas, near Rushville, assume the form of mud cones; and others, in the valley of the Ohio, in Virginia, and on the Kentucky river, also contain chloride of sodium, and are there connected with weak naphtha springs. But on the other side of the Caribbean Sea, on the north coast of South America, 11 miles south-south-east from the harbour of Cartagena de Indias, near the pleasant village of Turbaco, a remarkable group of salses or mud-volcanoes exhibits phenomena, which I was the first to describe.

In the neighbourhood of Turbaco, where one enjoys a magnificent view of the colossal snowy mountains (Sierras Nevadas) of Santa Marta, on a desert spot in the midst of the primeval forest, rise the Volcancitos, to the number of 18 or 20. The largest of the cones, which consist of blackish gray loam, are from 19 to 23 feet in height, and probably 80 feet in diameter at the base. At the apex of each cone is a circular orifice of 20 to 28 inches in diameter, surrounded by a small mud-wall. The gas rushes up with great violence, as in Taman, forming bubbles, each of which, according to my measurements in graduated vessels, contains 10-12 cubic inches. The upper part of the funnel is filled with

67 Sartorius von Waltershausen, Physisch-geographische Skizze von Island, 1847, s. 123; Bunsen "upon the processes of formation of the volcanic rocks of Iceland," Poggend. Annalen, Bd. lxxxiii, s. 257. 68 Waltershausen, op. cit. s. 118.

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