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Table of Contents

Position.—Name.—Mention of Etna by early writers.—Pindar.—Æschylus.—Thucydides.—Virgil.—Strabo.—-Lucretius.—Lucilius Junior.—Etna the home of early myths.—Cardinal Bembo.—Fazzello.—Filoteo.—Early Maps of the Mountain.—Hamilton.—Houel.—Brydone.—Ferrara.—Recupero.—Captain Smyth.—Gemellaro; his Map of Etna.—Elie de Beaumont.—Abich.—Hoffmann.—Von Waltershausen's Atlas des Aetna.—Lyell.—Map of the Italian Stato Maggiore.—Carlo Gemellaro.—Orazio Silvestri.

The principal mountain chain of Sicily skirts the North and a portion of the North-eastern coast, and would appear to be a prolongation of the Apennines. An inferior group passes through the centre of the island, diverging towards the South, as it approaches the East coast. Between the two ranges, and completely separated from them by the valleys of the Alcantara and the Simeto, stands the mighty mass of Mount Etna, which rises in solitary grandeur from the eastern sea-board of the island. Volcanoes, by the very mode of their formation, are frequently completely isolated; and, if they are of any magnitude, they thus acquire an imposing contour and a majesty, which larger mountains, forming parts of a chain, do not possess. This specially applies to Etna. "Cœlebs degit," says Cardinal Bembo, "et nullius montis dignata conjugium, caste intra suos terminos continetur." It is not alone the conspicuous appearance of the mountain which has made it the most famous volcano either of ancient or modern times:—the number and violence of its eruptions, the extent of its lava streams, its association with antiquity, and its history prolonged over more than 2400 years, have all tended to make it celebrated.

The geographical position of Etna was first accurately determined by Captain Smyth in 1814. He estimated the latitude of the highest point of the bifid peak of the great crater at 37° 43' 31" N.; and the longitude at 15° East of Greenwich. Elie de Beaumont repeated the observations in 1834 with nearly the same result; and these determinations have been very generally adopted. In the new Italian map recently constructed by the Stato Maggiore, the latitude of the centre of the crater is stated to be 37° 44' 55" N., and the longitude 44' 55" E. of the meridian of Naples, which passes through the Observatory of Capo di Monte.

According to Bochart the name of Etna is derived from the Phœnician athana—a furnace; others derive it from αι′θω—to burn. Professor Benfey of Gottingen, a great authority on the subject, considers that the word was created by one of the early Indo-Germanic races. He identifies the root ait with the Greek αι′θ and the Latin aed—to burn, as in aes-tu. The Greek name Αιτνα was known to Hesiod. The more modern name, Mongibello, by which the mountain is still commonly known to the Sicilians, is a combination of the Arabic Gibel, and the Italian Monte. During the Saracenic occupation of Sicily, Etna was called Gibel Uttamat—the mountain of fire; and the last syllables of Mongibello are a relic of the Saracenic name. A mountain near Palermo is still called Gibel Rosso—the red mountain; and names may not unfrequently be found in the immediate neighbourhood of Etna which are partly, or sometimes even entirely, composed of Arabic words; such, for example, as Alcantara—the river of the bridge. Etna is also often spoken of distinctively as Il Monte—the mountain par excellence; a name which, in its capacity of the largest mountain in the kingdom of Italy, and the loftiest volcano in Europe, it fully justifies.

Etna is frequently alluded to by classical writers. By the poets it was sometimes feigned to be the prison of the giant Enceladus or Typhon, sometimes the forge of Hephaistos, and the abode of the Cyclops.

It is strange that Homer, who has so minutely described certain portions of the contiguous Sicilian coast, does not allude to Etna. This has been thought by some to be a proof that the mountain was in a quiescent state during the period which preceded and coincided with the time of Homer.

Pindar (b.c. 522-442) is the first writer of antiquity who has described Etna. In the first of the Pythian Odes for Hieron, of the town of Aitna, winner in the chariot race in b.c. 474, he exclaims:

. . . "He (Typhon) is fast bound by a pillar of the sky, even by snowy Etna, nursing the whole year's length her dazzling snow. Whereout pure springs of unapproachable fire are vomited from the inmost depths: in the daytime the lava-streams pour forth a lurid rush of smoke; but in the darkness a red rolling flame sweepeth rocks with uproar to the wide deep sea . . . That dragon-thing (Typhon) it is that maketh issue from beneath the terrible fiery flood."[1]

Æschylus (b.c. 525-456) speaks also of the "mighty Typhon," (Prometheus V.):

. . . . . "He lies

A helpless, powerless carcase, near the strait

Of the great sea, fast pressed beneath the roots

Of ancient Etna, where on highest peak Hephæstos sits and smites his iron red hot, From whence hereafter streams of fire shall burst, Devouring with fierce jaws the golden plains Of fruitful, fair Sikelia."[2]

Herein he probably refers to the eruption which had occurred a few years previously (b.c. 476).

Thucydides (b.c. 471-402) alludes in the last lines of the Third Book to several early eruptions of the mountain in the following terms: "In the first days of this spring, the stream of fire issued from Etna, as on former occasions, and destroyed some land of the Catanians, who live upon Mount Etna, which is the largest mountain in Sicily. Fifty years, it is said, had elapsed since the last eruption, there having been three in all since the Hellenes have inhabited Sicily."[3]

Virgil's oft-quoted description of the mountain (Eneid, Bk. 3) we give in the spirited translation of Conington:

"But Etna with her voice of fear

In weltering chaos thunders near.

Now pitchy clouds she belches forth

Of cinders red, and vapour swarth;

And from her caverns lifts on high

Live balls of flame that lick the sky:

Now with more dire convulsion flings

Disploded rocks, her heart's rent strings,

And lava torrents hurls to-day

A burning gulf of fiery spray."

Many other early writers speak of the mountain, among them Theokritos, Aristotle, Ovid, Livy, Seneca, Lucretius, Pliny, Lucan, Petronius, Cornelius Severus, Dion Cassius, Strabo, Diodorus Siculus, and Lucilius Junior. Seneca makes various allusions to Etna, and mentions the fact that lightning sometimes proceeded from its smoke.

Strabo has given a very fair description of the mountain. He asserts that in his time the upper part of it was bare, and covered with ashes, and in winter with snow, while the lower slopes were clothed with forests. The summit was a plain about twenty stadia in circumference, surrounded by a ridge, within which there was a small hillock, the smoke from which ascended to a considerable height. He further mentions a second crater. Etna was commonly ascended in Strabo's time from the south-west.

While the poets on the one hand had invested the mountain with various supernatural attributes, and had made it the prison-house of a chained giant, and the workshop of a swart god, Lucretius endeavoured to show that the eruptions and other phenomena could be easily explained by the ordinary operations of nature. "And now at last," he writes, "I will explain in what ways yon flame, roused to fury in a moment, blazes forth from the huge furnaces of Aetna. And, first, the nature of the whole mountain is hollow underneath, underpropped throughout with caverns of basalt rocks. Furthermore, in all caves are wind and air, for wind is produced when the air has been stirred and put in motion. When this air has been thoroughly heated, and, raging about, has imparted its heat to all the rocks around, wherever it comes in contact with them, and to the earth, and has struck out from them fire burning with swift flames, it rises up and then forces itself out on high, straight through the gorges; and so carries its heat far, and scatters far its ashes, and rolls on smoke of a thick pitchy blackness, and flings out at the same time stones of prodigious weight—leaving no doubt that this is the stormy force of air. Again, the sea, to a great extent, breaks its waves and sucks back its surf at the roots of that mountain. Caverns reach from this sea as far as the deep gorges of the mountain below. Through these you must admit [that air mixed up with water passes; and] the nature of the case compels [this air to enter in from that] open sea, and pass right within, and then go out in blasts, and so lift up flame, and throw out stones, and raise clouds of sand; for on the summit are craters, as they name them in their own language, what we call gorges and mouths."[4]

These ideas were developed by Lucilius Junior in a poem consisting of 644 hexameters entitled Aetna. The authorship of this poem has long been a disputed point; it has been attributed to Virgil, Claudian, Quintilius Varus, Manilius, and, by Joseph Scaliger[5] and others, to Cornelius Severus. Wensdorff was the first to adduce reasons for attributing the poem to Lucilius Junior, and his views are generally adopted. Lucilius Junior was Procurator of Sicily under Nero, and, while resident in the Island, he ascended Etna; and it is said that he proposed writing a detailed history of the mountain. He adopted the scientific opinions of Epicurus, as established in Rome by Lucretius, and was more immediately a disciple of Seneca. The latter dedicated to him his Quæstiones Naturales, in which he alludes more than once to Etna. M. Chenu speaks of the poem of Lucilius Junior as "sans doute très-póetique, mais assez souvent dur, heurté, concis, et parcela même, d'une obscurité parfois désespérante."[6] At the commencement of the poem, Lucilius ridicules the ideas of the poets as regards the connection of Etna with Vulcan and the Cyclops. He has no belief in the practice, which apparently prevailed in his time, of ascending to the edge of the crater and there offering incense to the tutelary gods of the mountain. He adopts to a great extent the tone and style of Lucretius, in his explanation of the phenomena of the mountain. Water filters through the crevices and cracks in the rocks, until it comes into contact with the internal fires, when it is converted into vapour and expelled with violence. The internal fires are nourished by the winds which penetrate into the mountain. He traces some curious connection between the plants which grow upon the mountain, and the supply of sulphur and bitumen to the interior, which is, at best, but partly intelligible.

"Nunc superant, quacunque regant incendia silvæ

Quæ flammis alimenta vacent, quid nutriat Aetnam.

Incendi patiens illis vernacula caulis

Materia, appositumque igni genus utile terræ est,

Uritur assidue calidus nunc sulfuris humor,

Nunc spissus crebro præbetur flumine succus,

Pingue bitumen adest, et quidquid cominus acres

Irritat flammas; illius corporis Ætna est.

Atque hanc materiam penitus discurrere fontes

Infectæ erumpunt et aquæ radice sub ipsa."

Many of the myths developed by the earlier poets had their home in the immediate neighbourhood, sometimes upon the very sides, of Etna—Demeter seeking Persephone; Acis and Galatea; Polyphemus and the Cyclops. Mr. Symonds tells us that the one-eyed giant Polyphemus was Etna itself, with its one great crater, while the Cyclops were the many minor cones. "Persephone was the patroness of Sicily, because amid the billowy corn-fields of her mother Demeter, and the meadow-flowers she loved in girlhood, are ever found sulphurous ravines, and chasms breathing vapour from the pit of Hades."[7]

It is said that both Plato and the Emperor Hadrian ascended Etna in order to witness the sunrise from its summit. The story of

"He who to be deemed

A god, leaped fondly into Etna flames,

Empedokles"

is too trite to need repetition. A ruined tower near the head of the Val del Bove, 9,570 feet above the sea, has from time immemorial been called the Torre del Filosofo, and is asserted to have been the observatory of Empedokles. Others regard it as the remains of a Roman tower, which was possibly erected on the occasion of Hadrian's ascent of the mountain.

During the Middle Ages Etna is frequently alluded to, among others by Dante, Petrarch, Boccaccio, and Cardinal Bembo. The latter gives a description of the mountain in the form of a dialogue, which Ferrara characterises as "erudito, e grecizzante, ma sensa nervi." He describes its general appearance, its well-wooded sides, and sterile summit. When he visited the mountain it had two craters about a stone's throw apart; the larger of the two was said to be about three miles in circumference, and it stood somewhat above the other.[8]

In 1541 Fazzello made an ascent of the mountain, which he briefly describes in the fourth chapter of his bulky volume De Rebus Siculis.[9] This chapter is entitled "De Aetna monte et ejus ignibus;" it contains a short history of the mountain, and some mention of the principal towns which he enumerates in the following order: Catana, Tauromenium, Caltabianco, Linguagrossa, Castroleone, Francavilla, Rocella, Randatio (Randazzo), Bronte, Adrano, Paterno, and Motta. Fazzello speaks of only one crater.

In 1591 Antonio Filoteo, who was born on Etna, published a work in Venice in which he describes the general features of the mountain, and gives a special account of an eruption which he witnessed in 1536.[10] The mountain was then, as now, divided into three Regions. The first and uppermost of these, he asserts, is very arid, rugged, and uneven, and full of broken rocks; the second is covered with forests; and the third is cultivated in the ordinary manner. Of the height he remarks, "Ascensum triginta circiter millia passuum ad plus habet." In regard to the name, Mongibello, he makes a curious error, deriving it from Mulciber, one of the names of Vulcan, who, as we have seen, was feigned by the earlier poets to have had his forge within the mountain.

In 1636 Carrera gave an account of Etna, followed by that of the Jesuit Kircher, in 1638. The great eruption of 1669 was described at length by various eye-witnesses, and furnished the subject of the first detailed description of the eruptive phenomena of the mountain. Public attention was now very generally drawn to the subject in all civilised countries. It was described by the naturalist, Borelli, and in our own Philosophical Transactions. Lord Winchelsea, our ambassador at Constantinople, was returning to England by way of the Straits of Messina at the time of the eruption, and he forwarded to Charles II "A true and exact relation of the late prodigious earthquake and eruption of Mount Ætna, or Monte Gibello."

The first map of the mountain which we have been able to meet with, was published in reference to the eruption of 1669; it is entitled, "Plan du Mont Etna communenent dit Mount Gibel en l'Isle de Scicille et de t'incedie arrive par un treblement de terre le 8me Mars dernier 1669." This plan is in the Bibliothèque Nationale, in Paris; it was probably drawn from a simple description, or perhaps altogether from the imagination, as it is utterly unlike the mountain, the sides of which possess an impossible steepness. Another very inaccurate map was published in Nuremberg about 1680, annexed to a map of Sicily, which is entitled, "Regnorum Siciliæ et Sardiniæ, Nova Tabula." Again, in 1714 H. Moll, "geographer in Devereux Street, Strand," published a new map of Italy, in which there is a representation of Etna during the eruption of 1669. This also was probably drawn from the imagination; no one who has ever seen the mountain would recognise it, for it has a small base, and sides which rival the Matterhorn in abruptness. Over against the coast of Sicily, and near the mountain, is written:—"Mount Etna, or Mount Gibello. This mountain sometimes issues out pure flame, and at other times a thick smoak with ashes; streams of fire run down with great quantities of burning stones, and has made many eruptions."

During the eighteenth century Etna was frequently ascended, and as frequently described. We have the accounts of Massa (1703), Count D'Orville (1727), Riedesel (1767), Sir William Hamilton (1769), Brydone (1776), Houel (1786), Dolomieu (1788), Spallanzani (1790), and many minor writers, such as Borch, Brocchi, Swinburne, Denon, and Faujas de Saint Fond. There is great sameness in all of these narratives, and much repetition of the same facts; some of them, however, merit a passing notice.

Sir William Hamilton's Campi Phlegræi relates mainly to Vesuvius and the surrounding neighbourhood; but one of the letters "addressed to the Secretary of the Royal Society on October 17th, 1769," describes an ascent of Etna. Hamilton ascended on June 24th with the Canon Recupero and other companions; the few observations of any value which he made have been alluded to elsewhere under the head of the special subjects to which they refer. The illustrations of the Campi Phlegræi, specially the original water-colours which are contained in one of the British Museum copies, are magnificent, and convey a better idea of volcanic phenomena than any amount of simple reading. From them we can well realise the opening of a long rift extending down the sides of a mountain during its eruption, and the formation of subsidiary craters along the line of fire thus opened. Various volcanic products are also admirably painted. In the picture of Etna, however, which was drawn by Antonio Fabris, the artist has scarcely been more successful than his predecessors, and the slope of the sides of the mountain has been greatly exaggerated.

M. Houel, in his Voyage pittoresque dans les Deux Siciles, 1781-1786, has given a fairly good account of Etna, accompanied by some really excellent engravings.

In 1776 Patrick Brydone, a clever Irishman with a good deal of native shrewdness and humour, published two volumes of a Tour in Sicily and Malta, in which he devoted several chapters to Mount Etna. He made the ascent of the mountain, and collected from the Canon Recupero, and from others, many facts concerning its then present, and its past history. He also made observations as to the height, temperature of the air at various elevations, brightness of the stars, and so on. Sir William Hamilton calls Brydone "a very ingenious and accurate observer," and adds that he was well acquainted with Alpine measurements. M. Elie de Beaumont, writing in 1836, speaks of him as le celebre Brydone; while, on the other hand, the Abbé Spallanzani, displeased at certain remarks which he made concerning Roman Catholicism in Sicily, never fails to deprecate his work, and deplores "his trivial and insipid pleasantries." Albeit Brydone's chapters on Etna furnished a more complete account of the volcano than any which had appeared in English up to that time; his remarks are frequently very sound and just, and we shall have occasion more than once to quote him.

It was reserved, however, for the Abate Francesco Ferrara, Professor of Physical Science in the University of Catania, to furnish the first history of Etna and of its eruptions, which had any just claim to completeness. It is entitled, Descrizione dell' Etna, con la Storia delle Eruzioni e il Catalogo del prodotti. The first edition appeared in 1793, and a second was printed in Palermo in 1818. The author had an enthusiastic love for his subject:—"Nato sopra l'Etna," he writes, "che io conobbi ben presto palmo a palmo la mia passione per lo studio fissò la mia attenzione sul bello, e terribile fenomeno che avea avanti agli occhi." The work commences with a general description of the mountain—its height, the temperature of the different regions, the view from the summit, the mass, the water-springs, the vegetable and animal life, and the internal fires. This extends over sixty-nine octavo pages. The second part of the book—eighty pages—gives a history of the eruptions from the earliest times to the year 1811; the third part—sixty-seven pages—treats of the nature of the volcanic products; and the fourth part—thirty-four pages—discusses certain geological and physical considerations concerning the mountain. At the end there are a few badly drawn and engraved woodcuts, and a map which, although the trend of the coast-line is quite wrong, is otherwise fairly good. The engravings represent the mountain as seen from Catania; the Isole dei Ciclopi, and the neighbouring coast; the Montagna della Motta; and a view from Catania of the eruption of 1787. This work has evidently to a great extent been a labour of love; it is full of personal observations, and also embodies the results of many other observers. It has furnished the foundation of much that has since been written concerning Etna.

The Canon Recupero has been alluded to above; he accompanied Hamilton, Brydone, and others to the summit of the mountain, and he was employed by the Government to report on the flood which, in 1755, descended with extraordinary violence through the Val del Bove. Beyond this, Recupero does not appear to have published anything concerning Etna, although it was well known that he had plenty of materials. He died in 1778, and it was not till the year 1815 that his results were published under the title of Storia Naturale et Generale dell' Etna, del Canonico Giuseppe Recupero.—Opera Postuma. This work consists of two bulky quarto volumes, the first of which is devoted to a general description of the mountain, the second to a history of the eruptions, and an account of the products of eruptions. Some idea may be formed of the extreme prolixity of the author if we mention that two chapters, together containing twelve quarto pages, are devoted to the discussion of the height of Etna, while the first volume is terminated by sixty-three closely printed pages of annotations. A few rough woodcuts accompany the volumes; a view of the mountain which, as usual, is out of all reason as regards abruptness of ascent, and a carta oryctographia di Mongibello in which the trend of the coast-line between Catania and Taormina is altogether inexact, complete the illustrations of this most detailed of histories.

During the years 1814-1816 Captain Smyth, acting under orders from the Admiralty, made a survey of the coast of Sicily, and of the adjacent islands. At this time the Mediterranean charts were very defective; some places on the coast of Sicily were mapped as much as twenty miles out of their true position, and even the exact positions of the observatories at Naples, Palermo, and Malta were not known. Among other results, Smyth carefully determined the latitude and longitude of Etna, accurately measured its height, and examined the surroundings of the mountain. His results were published in 1824, and are often regarded as the most accurate that we possess.

In 1824 Dr. Joseph Gemellaro, who lived all his life on the mountain, and made it his constant study, published an "Historical and Topographical Map of the Eruptions of Etna from the era of the Sicani to the year 1824." In it he delineates the extent of the three Regions, Coltivata, Selvosa, and Deserta; he places the minor cones, to the number of seventy-four, in their proper places, and he traces the course of the various lava-streams which have flowed from them and from the great crater. This map is the result of much patient labour and study, and it is a great improvement upon those of Ferrara and Recupero, but of course it is impossible for one man to survey with much accuracy an area of nearly 500 square miles, and to trace the tortuous course of a large number of lava-streams. Hence we must be prepared for inaccuracies, and they are not uncommon—the coast line is altogether wrong as to its bearings, some of the small towns on the sides of the mountain are misplaced, and but little attention has been paid to scale. Still the map is very useful, as it is the only one which shows the course of the lava-streams.

Mario Gemellaro, brother of the preceding, made almost daily observations of the condition of Etna, between the years 1803 and 1832. These results were tabulated, and they are given in the Vulcanologia dell' Etna of his brother, Professor Carlo Gemellaro, under the title of Registro di Osservazioni del Sigr. Mario Gemellaro.

Carlo Gemellaro contributed many memoirs on subjects connected with the mountain. They are chiefly to be found in the Atti dell' Accademia Gioenia of Catania, and they extend over a number of years. Perhaps the most important is the treatise entitled "La Vulcanologia dell' Etna che comprende la Topographia, la Geologia, la Storia, delle sue Eruzioni." It was published in Catania in 1858, and is dedicated to Sir Charles Lyell, who ascended the mountain under the guidance of the author. The latter also published a Breve Raggualio della Eruzione dell' Etna, del 21 Agosto 1852, which contains the most authentic account of this important eruption, accompanied by some graphic sketches made on the spot. The last contribution of Carlo Gemellaro to the history of Etna, is fitly entitled Un Addio al Maggior Vulcano di Europa. It was published in 1866, and with pardonable vanity the author reviews his work in connection with the mountain, extending over a period of more than forty years. He commences his somewhat florid farewell with the following apostrophe:—"O Etna! splendida e perenne manifestazione della esistenza dei Fuochi sotteranei massimo fra quanti altri monti, dalle coste meridionali di Europa, dalle orientali dell' Asia e delle settentrionali dell' Africa si specchiano nel Mediterraneo: tremendo pei tuoi incendii: benigno per la fertilità del vulcanico tuo terreno ridotto a prospera coltivazione . . . io, nato appiè del vasto tuo cono, in quella Città che hai minacciato più d'una volta di sepellire sotto le tue infocate correnti: allogato, nella mia prima età, in una stanza della casa paterna, che signoreggiava in allora più basse abizioni vicine, ed intiera godeva la veduta della estesa parte meridionalè della tua mole, io non potera non averti di continuo sotto gli occhi, e non essere spettatore dei tuoi visibili fenomeni!"

In 1834, M. Elie de Beaumont commenced a minute geological examination of the mountain. His results were published in 1838, under the title of Recherches sur la structure et sur l'origine du Mont Etna, and they extend over 225 pages.[11] He re-determined the latitude and longitude of the mountain, measured the slope of the cone, and the diameter of the great crater, and minutely examined the structure of the rocks at the base of the mountain. He also gives a good sectional view, elevations taken from each quarter of the compass, and a geological map, which although accurate in its general details, can scarcely be considered very satisfactory. A relief map of Etna, a copy of which is in the Royal School of Mines, was afterwards constructed from the flat map, and this was, we believe, at the same time, the first geological map, and the first map in relief, which had been made of the mountain. Elie de Beaumont considers granite as the basis of the mountain, because it is sometimes ejected from the crater; old basaltic rocks appear in the Isole dei Ciclopi, and near Paterno, Licodia, and Aderno; cailloux roulés near Motta; ancient lavas on each side of the Val del Bove; modern lavas in every part of the mountain, and calcareous and arenaceous rocks in the surrounding mountains.

In 1836, Abich published some excellent sections of Etna, and an accurate view of the interior of the crater, in a work entitled Vues illustratives de quelques Phénomènes Géologiques prises sur le Vésuve et l'Etna pendant les années 1833 and 1834.

The whole of the thirteenth volume (1839) of the Berlin Archiv für Mineralogie, Geognosie, Berghau und Hüttenkunde, is occupied by an elaborate memoir on the geology of Sicily[12] by Friedrich Hoffmann, accompanied by an excellent geological map. A long account of the geology of Etna is given, and an enlarged map of the mountain was afterwards constructed and published in the Vulkanen Atlas of Dr. Leonhard in 1850.[13]

In 1836 Baron Sartorius Von Waltershausen commenced a minute survey of Etna, preparatory to a complete description of the mountain, both geological and otherwise. He was assisted by Professor Cavallari of Palermo, Professor Peters of Hensbourg, and Professor Roos of Mayence. The survey occupied six years, (1836-1842), and the results of direct observation in the form of maps and drawings, occupied a hundred sheets 160 millimetres (6¼ inches) long, by 133 m.m. (5¼ inches) broad. Twenty-nine separate points were made use of in the triangulation; and the scale chosen was 1 in 50,000. The results were published in a large folio atlas, which appeared in eight parts; the first in 1845 and the last in 1861, when the death of Von Waltershausen put an end to the further publication. There are 26 fine coloured maps, and 31 engravings. The cost of the atlas is £12. The maps are both geological and topographical, and they are accompanied by outline engravings of various details of special interest. The Atlas des Aetna furnishes the most exhaustive history of any one mountain on the face of the earth, and Sartorius Von Waltershausen will always be the principal authority on the subject of Etna.

Sir Charles Lyell visited Etna in 1824, 1857, and again in 1858. He embodied his researches in a paper presented to the Royal Society in 1859, and in a lengthy chapter in the Principles of Geology. His investigations have added much to our knowledge of the formation and geological characteristics of the mountain, especially of that part of it called the Val del Bove.

Later writers usually quote Von Waltershausen and Lyell, and do not add much original matter. The facts of all subsequent writers are taken more or less directly from these authors. The latest addition to the literature of the mountain, is the Wanderungen am Aetna of Dr. Baltzer, in the journal of the Swiss Alpine Club for 1874.[14]

A fine map of Sicily, on the unusually large scale of 1 in 50,000, or 1·266 inch to a mile, was constructed by the Stato Maggiore of the Italian government, between 1864 and 1868. The portion relating to Etna, and its immediate surroundings occupies four sheets. All the small roads and rivulets are introduced; the minor cones and monticules are placed in their proper positions, and the elevation of the ground is given at short intervals of space over the entire map. An examination of this map shows us that distances, areas, and heights, have been repeatedly misstated, the minor cones misplaced, and the trend of the coast line misrepresented. For example, if we draw a line due north and south through Catania, and a second line from the Capo di Taormina, (the north-eastern limit of the base of Etna), until it meets the first line at Catania, the lines, will be found to enclose an angle of 26°. If we adopt the same plan with Gemellaro's map, the included angle is found to be 53°, and in the case of the maps of Ferrara and Recupero more than 60°. Again, it has been stated on good authority, that the lava of 396 b.c. which enters the sea at Capo di Schiso flowed for a distance of nearly 30 miles; the map shows us that its true course was less than 16 miles. Lyell in 1858 gives a section of the mountain from West 20° N., to East 20° S., but a comparison with the new map proves that the section is really taken from West 35° N. to East 35° S., an error which at a radius of ten miles from the crater would amount to a difference of nearly three miles.

The mantle of Carlo Gemellaro appears to have fallen upon Cav. Orazio Silvestri, Professor of Chemistry in the University of Catania. He has devoted himself with unwearying vigour to the study of the mountain, and his memoirs have done much to elucidate its past and present history. His most recent work of importance on the subject is entitled I Fenomeni Vulcanici presentati dall' Etna nel 1863-64-65-66. It was published in Catania in 1867, and contains an account of some very elaborate chemico-geological researches.