ITALIA. around which sweeps the great chain of the Alps, fiii-ming a continuous barrier from the shores of the Mediterranean near JIassiha to the head of the Adriatic at Trieste (Tergeste). From the western extremity of this vast mountain cliain, where the ranges of the JIaritime Alps abut immediately on the sea-shore, branches off the inferior, but still very considerable, chain of the Apennines, which, after sweeping round the Ligurian gulf, stretches in an unbroken line directly across to the shores of the Adriatic, and then, turning abruptly to the SE., di- vides the whole peninsula throughout its entire length, until it ends in the promontory of Leuco- petra, on the Sicilian sea. [Apenmnus.] The precise limits of Italy can thus only be doubt- ful on its northern frontier, where the massive ranges of the Alps, though presenting, when viewed on the large scale, a vast natural barrier, are in fact in dented and penetrated by deep and irregular valleys, which render it often difficult to determine the natural boundary; nor has this been always adopted as tlie jiolitical one. Along the coast of Liguria, between Massilia and Genua, the Maritime Alps send down successive ranges to the sea, forming great headlands, of which the most striking are : that be- tween Nuiiixnd Finale, commonly regarded by modern geographers as the termination of the JIarilime Alps ; and the promontory immediately W. of J/o- tiaco, which still bears the remains of the Tropaea Augusti, and the passage of which presents the greatest natural difficulties to the construction of a road along this coast. This mountain headland would probably be the best point to fix as the natural limit of Italy on this side, and appears to have been commonly regarded in ancient times as such ; but when Augustus first extended the political limits of Italy to the foot of the Alps, he found it convenient to carry them somewhat further W., and fixed on the river Varus as the boundary; thus including Xicaea, which was a colony of Massilia, and hnd previously been considered as belonging to Gaul. (Strab. iv. pp. 178, 18-t, v. p. 209;>lin. iii. 4. s. 5, .5. s. 6, 7; Mela, ii. 4. § 9; Ptol. iii. 1 § 1; Lucan, i. 404.) Though this demarcation does not appear to have been always followed; for in the Itinerary of Anto- ninus (p. 296) we again find the Al])is Maritima (meaning the mountain headland above described) fixed as the boundary between Italy and Gaul : it was generally adopted, and has continued without alteration to the present day. The extreme NE. limit of Italy, at the head of the Adriatic Gulf, is equally susceptible of various determination, and here also Augustus certainly transgressed the natural limits by including Istria within the confines of Italy. (Plin. iii. 18. s. 22 ; Strab. V. p. 209, vii. p. 314".) But here, also, the reasons of political convenience, which first gave rise to this extension, have led to its subsequent adoption, and Istria is still commonly reckoned a part of Italy. The little river Formio, which flows into the Adriatic between Trieste and Capo d' Istria, was previously established as the boimdary of Italy on this side : but the range of the Juhan Alps, which, after sweeping round the broad plain of the Frioul, sud- denly approaches close to the Adriatic, near the sources of the Timavus, and presents a continuous mountain barrier from thence to Trieste, would seem to con- stitute the time natural limit. Even between these two extremities, the chain of the Alps does not always form so simple and clearly- marked a frontier as might at first be expected. It ITALIA. 77 would not, indeed, be difficult to trace geographicallv such a line of boundary, by following the water-shed or line of highest ridge, throughout : but the im- perfect knowledge of the Alps possessed by the ancients was scarcely sufficient for such a pui-pose ; and this line was not, in ancient, any more than in modern times, the actual limit of different nation- ahties. Thus, the Ehaetians, who in the days of Strabo and Pliny were not comprised in Italv, inhabited the valleys and lower ridges of the Alps on the S. side of the main chain, down quite to the borders of the plains, as well as the northern decli- vities of the same mountains. Hence, a part of the Southern Tirol, including the valley of the Adiije above Trent, and apparently the whole of the 1 'al- tcline, though situated on the scuthern side of the Alps, were at that time excluded from Italy : while, at a later period, on the contrary, the two provinces of Khaetia Prima and lihaetia Secunda were both incorporated with Italy, and the boundary, in con- sequence, can-ied far to the N. of the central line of geographical limit. In like manner the Cottian Alps, which formed a separate district, under a tri- butary chieftain, in the days of Augustus, and were only incorporated with Italy by Nero, comprised the valleys on both sides of the main chain ; and the provinces established in the latter periods of the Empire under the names of the Alpes Cottiae and Alpes Maritimae, appear to have been constituted with equally little reference to this natural boundary. (Walckenaer, Geogr. des Gaules, vol. ii. pp. 21 — 3G, 361,395.) While Italy is bounded on the N. by the great natural barrier of the Alps, it is to the chain of the Apennines, by which it is traversed in its entire length, that it mainly owes its peculiar configuration. This great mountain chain may be considered as the back-bone or vertebral column of the Italian pen- insula, wjiich sends down offsets or lateral ridges on both sides to the sea, while it forms, throughout its long course, the water-shed or dividing ridire, from which the rivers of the peninsula take their rise. A detailed description of the Apennines has already been given under the article Apennixus : they are here noticed only as far as they are con- nected with the general features of the physical geography of Italy. 1. Northern Italy. — The first part of the chain of the Apennines, which extends from the point of their junction with the Maritime Alps along the N. shore of the Gulf of Genoa, and from thence across the whole breadth of Italy to the Adriatic near Ariminum, constitutes the southern boundary of a great valley or plain, which extends, without interruption, from the foot of the Apennines to that of the Alps. This broad expanse of perfectly level country, consisting throughout of alluvial soil, is watered by the great river Padus, or Pa, and its numerous tributaries, which bring down the waters from the flanks both of the Alps and Apennines, and render this extensive plain one of tbe most fertile tracts in Europe. It extends through a space of above 200 geog. miles in length, but does not exceed 50 or 60 in breadth, until it approaches the Adriatic, where the Alps beyond Vicenza trend away rapidly to the northward, sweeping in a semicircle round the plains of the Fnuli (which are a mere continuation of the great plain of the Po), until they again approach the Adriatic near Trieste. At the same time the Apennines also, as they approach towards the Adriatic, gradually recede from" the
