where the sea-bottom sinks rapidly down towards the eastern
basin of the Mediterranean, steep rocky coasts prevail except
opposite the plain of Catania. In the northern half of this coast
the lava streams of Mount Etna stand out for a distance of about
20 m. in a line of bold cliffs and promontories. At various points
on the east, north and west coasts there are evidences of a rise
of the land having taken place within historical times, at Trapani
on the west coast even within the 19th century. As in the rest
of the Mediterranean, tides are scarcely observable; but at
several points on the west and south coasts a curious oscillation
in the level of the waters, known to the natives as the marrobbio
(or marobia), is sometimes noticed, and is said to be always
preceded by certain atmospheric signs. This consists in a sudden
rise of the sea-level, occasionally to the height of 3 ft., sometimes
occurring only once, sometimes repeated at intervals of a minute
for two hours, or even, at Mazzara, where it is most frequently
observed, for twenty-four hours together.
The surface of Sicily lies for the most part more than 500 ft above the level of the sea. Caltanissetta, which occupies the middle point in elevation as well as in respect of geographical situation, stands 1900 ft. above sea-level. Considerable mount- ains occur only in the north, where the lower slopes of all the heights form one continuous series of olive-yards and orangeries. Of the rest of the island the greater part forms a plateau varying in elevation and mostly covered with wheat-fields. The only plain of any great extent is that of Catania, watered by the Simeto, in the east; to the north of this plain the active volcano of Etna rises with an exceedingly gentle slope to the height of 10,868 ft. from a base 400 sq. m. in extent. This is the highest elevation of the island. The steep and narrow crystalline ridge which trends north-eastwards, and is known to geographers by the name of the Peloritan Mountains, does not reach 4000 ft. The Nebrodian Mountains, a limestone range connected with the Peloritan range and having an east and west trend, rise to a somewhat greater height, and farther west, about the middle of the north coast, the Madonie (the only one of the groups mentioned which has a native name) culminate at the height of nearly 6500 ft. From the western end of the Nebrodian Mountains a lower range (in some places under 1500 [ft. in height) winds on the whole south-eastwards in the direction of Cape Passaro. With the exception of the Simeto, the principal perennial streamsâ€” the Salso, the Platani and the Beliceâ€” enter the sea on the soutli coast.
Geology*â€” In general, the older beds occur along the northern coast, and progressively newer and newer beds are found towards the south Folding, however, has brought some of the older beds to the surface in the hills which lie to the north and north-east of sciacca. I he Monti Pelontani at the north-eastern extremity of the island consists of gneiss and crystalline schists; but with this ex- ception the whole of Sicily is formed of Mesozoic and later deposits the Tertiary beds covering by far the greater part. Triassic rocks lorm a discontinuous band along the northern coast, and are especially well developed in the neighbourhood of Palermo. They rise again to the surface in the southern part of the island, in the hills which , lie to the north of Sciacca and Bivona. In both areas thev are accompanied by Jurassic, and occasionally by Cretaceous, beds- but of the latter there are only a few small patches. In the south- eastern part of the island there are also a few very small outcrops of Mesozoic beds. The Eocene and Oligocene form a broad belt along the northern coast, very much more continuous than the Mesozoic band and from this belt a branch extends southwards to bciacca Another patch of considerable size lies to the east of r-iazza-Armenna. Miocene and Pliocene deposits cover nearly the whole of the country south of a line drawn from Etna to Marsala- and there is also a considerable Miocene area in the north about
Â£1!^ f" 1 jÂ£ amC u' avas , ?- nd a , shes of a recent geological period IM? no L onIy th u e wh Â°leof Etna but also a large part of the Monti
vn it e ?Â°c ut - h - Sraa " P atch es occur also at Pachino and in the hills north of Sciacca.
Climate .â€” The climate of Sicily resembles that of the other lands m the extreme south of Europe. As regards temperature, it has the warm and equable character which belongs to most of the Mediter- ranean region. At Palermo (where continuous observations have been made since 1791) the range of temperature between the mean of the coldest and that of the hottest month is little greater than at Greenwich. The mean temperature of January (5ifÂ°F ) is neariv ^'^Vl^f of o 0ctober Â« the south of England that of (77 F.) about 13Â° warmer than the corresponding month at Green wich. In only seven of the thirty years, l8 7 i-l|oo, was the tier mometer observed to sink below the freezing-point; frost thus occurs in the island even on the low grounds, though never for more than a few hours. On the coast snow is seldom seen, buITt <wÂ£5 occasionally. On the Madonie it lies tiUJune, on EtL tmjulv
Toln TnH ram - a11 ^ C6pt Â° n th f h u igher â„¢Â°untains does not reach 30 m., and as in other parts of the extreme south of Eurooek occurs chiefly ln the winter months, while the three months (Tune July and August) are almost quite dry. During these Months the whole rainfall does not exceed 2 in., except on the slorfes of the
s m umme a r ln T n h P th v n r h - eaSt -- *Â¥"? m Â° St of * he streamsTy up tn summer. The chief scourge is the sirocco, which is experienced in its most characteristic form on the north coast, as an oppressive narch
at^ dry Wmd - ^Â° win u g Strongl y and steadil y frÂ° P n? thTIouth the atmosphere remaining through the whole period of its duration leaden-coloured and hazy in consequence of the presence of immense Quantities of reddish dust. It occurs most frequently fn ApT and then m May and September, but no month is entirety Lefrom "t Three days are the longest period for which it lasts. The same Tame is some tl rnes applied to a moist and not very hot, but vet oppressive south-east wmd wh.ch blows from time to time on the east coS' Malaria occurs in some parts of the island.
Mora.â€” The flora of Sicily is remarkable for its wealth of species- but comparing Sicily with other islands that have been long^a*: ated from the mainland, the number of endemic species is not Seat The orders most abundantly represented are the Comtositae CrZ)' ferae Labiatae Caryophyllaceae and ScrophulartceaT^heRofaclae
fpecfesVth U e n ros n p tly Th PreSented ' and "Tl* them are numerous species ot the rose. The general aspect of the vegetation of Sirilv
however has been greatly affected, as in other partfof the Medker' ranean, by the introduction of plants within historicaHimes Be'ng more densely populated than any other large Mediterranean island and haying its population dependent chiefly on the products of the soil it is necessarily more extensively cultivated than any other of the larger islands referred to, and many of the objects 01 cultivation are not originally natives of the island. Not to mention the oliw which must have been introduced at a remote perio d, a"l he memblrs of the orange tribe, the agave and the prickly pear as welUsTher plants highly characteristic of Sicilian scenery^ nave blel introduced since the beginning of the Christian era. With respect to vSefatiâ„¢ and cultivation three zones may be distinguished. P The ^ firTtreaches to about 1600 ft above sea-level, the upper limit of the members of the orange tribe; the second ascends to about 3300 ft the Hmit of the growth of wheat, the vine and the hardier Evergreens ^d the th.rd, that of forests reaches from about 330^ ft upwards But it is not merely height that determines the genera character al ^ ege , ta VÂ° n - - The cultivated trees of Sicily moltiy demands uch an amount of moisture as can be obtained only on thelnount^n slopes, and it is worthy of notice that the structure of the rnolmtains is peculiarly favourable to the supply of this want. The Hmestones of which they are mostly composed act like a sponge abSrbW the rain-water through their innumerable pores and fissures and thuf storing it up in the interior, afterwards to allow it to well forth in SF â€¢ at , va y iOU ? Ovations lower down. In this way the rrfetion which is absolutely indispensable for the members of the orangf tribe tr nn Vu e - d - y S - eaSO - n is great] y facilitated, and even thosf trees for which irrigation ls not so indispensable receive a more amnk supply of moisture during the rainy season. Hence it Is that while the. plain of Catania is almost treeless and tr^-cultivation k comparat.vely imited in the west and south, where tte exWof knd under 1600 ft. is considerable, the whole of the north and north east Trrt f -Â° m * f he B u ay ,Â° f Castellammare round to Catania is an^ndle s
with oTvl^ T^l 8 ' m Which Â° ranges ' citrons and lemons alternate with olives, almonds, pomegranates, figs, carob trees, pistachfos
?7â„¢?t n lU?L Vl ?% ? he ,! imit in height of ^e oHve P s about ?,nâ„¢ = 'Â£Â« that Â° f the Vlne about 35O0 ft. The lemon is really grown upon a bitter orange tree, grafted to bear the lemon. A conriae^ able silk production depends on the cultivation of the nVulberrvTn the neighbourhood of Messina and Catania. Among othâ„¢ trees and shrubs may be mentioned the sumach, the date-pafm the plantani various bamboos, cycads and the dwarf-palm, the last of which !nT- S '.VT 6 Parts 0i - Sicil y more P rofus ely han anywhere else ve d et n h^ e n d T fa < te f r ? gi Â° n in the s Â°uth-west yields almolt the only vegetable product of importance. The A rundo Dcnax, the tallest of European grasses, is largely grown for vine-stakes.
A general account of the geology of the island will be found in L Baldacci, Descrizwne geologica dell' isola di Sicilia (Rome, 1886), Zta T 3 ?;. |, Â°?',. fuller an d later information reference should be made to the publications of the Reale Comitato Geologico d'ltalia.
Population.â€” The area and population of the several provinces are shown m the table on the next page. Thus between 1881 and 1 901 the population increased at the rate of 20-5% The average density is extremely high for a country which lives almost exclusively by agriculture, and is much higher than the average for Italy in general, 293 per sq. m. In 1905 the popula- tion was 3,568,124, the rate of increase being only 4-4% per annum; the low rate is due to emigration.