Etna: A History of the Mountain and of its Eruptions

by G. F. Rodwell

Grotto delle Palombe near Nicolosi

The only important minor cone which has been produced during the historical period, is the double mountain known as Monti Rossi, from the red colour of the cinders which compose it. This was raised from the plain of Nicolosi during the eruption of 1669; it is 450 feet in height, and two miles in circumference at the base. In a line between the Monti Rossi and the great crater, thirty-three minor cones may be counted. Hamilton counted forty-four, looking down from the summit towards Catania, and Captain Smyth was able to discern fifty at once from an elevated position on the mountain. Many of these parasitic cones are covered with vegetation, as the names Monte Faggi, Monte Ilice, Monte Zappini, indicate. The names have not been happily chosen; thus there are several cones in different parts of the mountain called by the same name—Monte Arso, Monte Nero, Monte Rosso, Monte Frumento, are the most common of the duplicates. Moreover, the names have from time to time been altered, and it thus sometimes becomes difficult to trace a cone which has been alluded to under a former name, or by an author who wrote before the name was changed. In addition to the minor cones from which lava once proceeded, there are numerous smaller vents for the subterranean fires called Bocche, or if very small, Boccarelle, del Fuoco. In the eruption of 1669, thirteen mouths opened in the course of a few days; and in the eruption of 1809, twenty new mouths opened one after the other in a line about six miles long. Two new craters were formed in the Val del Bove in 1852, and seven craters in 1865. The outbursts of lava from lateral cones are no doubt due to the fact that the pressure of lava in the great crater, which is nearly 1000 feet in depth, becomes so great that the lava is forced out at some lower point of less resistance. The most northerly of the minor cones is Monte di Mojo, from whence issued the lava of 396 b.c., it is 11½ miles from the crater; the most southerly cone is Monte Ste Sofia, 16 miles from the crater. Nearly all the minor cones are within 10 miles of the crater, and the majority are collected between south-east, and west, that is, in an angular space of 135°, starting midway between east and south, (45° south of due east) to due west, (90° west of due south). Lyell speaks of the minor cones "as the most grand and original feature in the physiognomy of Etna."

A number of caverns are met with in various parts of Etna; Boccacio speaks of the Cavern of Thalia, and several early writers allude to the Grotto delle Palombe near Nicolosi. The latter is situated in front of Monte Fusara, and the entrance to it is evidently the crater of an extinct monticule. It descends for 78 feet, and at the bottom a cavern is entered by a long shaft; this leads to a second cavern, which abruptly descends, and appears to be continued into the heart of the neighbouring Monti Rossi. Brydone says that people have lost their senses in these caverns, "imagining that they saw devils, and the spirits of the damned; for it is still very generally believed that Etna is the mouth of Hell." Many of the caverns near the upper part of the mountain are used for storing snow, and sometimes as places of shelter for shepherds. We have already seen to what extent Lucretius attributed the eruptions to air pent up within the interior caverns of the mountains.

The surface of the mountain has been divided into three zones or regions—the Piedimontana or Coltivata; the Selvosa or Nemorosa; and the Deserta or Discoperta. Sometimes the name of Regione del Fuoco is given to the central cone and crater. As regards temperature, the zones correspond more or less to the Torrid, Temperate, and Frigid. The lowest of these, the Cultivated Region, yields in abundance all the ordinary Sicilian products. The soil, which consists of decomposed lava, is extremely fertile, although of course large tracts of land are covered by recent lavas, or by those which decompose slowly. In this region the vine flourishes, and abundance of corn, olives, pistachio nuts, oranges, lemons, figs, and other fruit trees.

The breadth of this region varies; it terminates at an approximate height of 2000 feet. A circle drawn with a radius of 10 miles from the crater, roughly defines the limit. The elevation of this on the north is 2,310 feet near Randazzo; on the south, 2,145 feet near Nicolosi; on the east, 600 feet near Mascali; and on the west, 1,145 feet near Bronte. The breadth of this cultivated zone is about 2 miles on the north, east, and west, and 9 or 10 on the south, if we take for the base of the mountain the limits proposed above.

The Woody Region commences where the cultivated region ends, and extends as a belt of varying width to an approximate height of 6,300 feet. It is terminated above by a circle having a radius of nearly 1½ miles from the crater. There are fourteen separate forests in this region: some abounding with the oak, beech, pine, and poplar, others with the chestnut, ilex, and cork tree.

The celebrated Castagno di Cento Cavalli, one of the largest and oldest trees in the world, is in the Forest of Carpinetto, on the East side of the mountain, five miles above Giarre. This tree has the appearance of five separate trunks united into one, but Ferrara declares that by digging a very short distance below the surface he found one single stem. The public road now passes through the much-decayed trunk. Captain Smyth measured the circumference a few feet from the ground, and found it to be 163 feet, which would give it a diameter of more than 50 feet. The tree derives its name from the story that one of the Queens of Arragon took shelter in its trunk with a suite of 100 horsemen. Near this patriarch are several large chestnuts, which, without a shadow of doubt, are single trees; one of these is 18 feet in diameter, and a second 15 feet, while the Castagno della Galea, higher up on the mountain, is 25 feet in diameter, and probably more than 1000 years old. The breadth of the Regione Selvosa varies considerably, as may be seen by reference to the accompanying map; in the direction of the Val del Bove it is very narrow, while elsewhere it frequently has a breadth of from 6 to 8 miles.

The Desert Region is embraced between the limit of 6,300 feet and the summit. It occupies about 10 square miles, and consists of a dreary waste of black sand, scoriæ, ashes, and masses of ejected lava. In winter it remains permanently covered with snow, and even in the height of summer snow may be found in certain rifts.