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GEOGRAPHY
Dalmatia'is the long line of arid limestone mountains, not “ the green Illyrian hills ” of the poet’s fancy, which, beginning with the massif of the Velebit, commanding Novigrad and Obrovaz, runs along the Dinaric crests till it reaches its highest point in Orjen, above the Bocche di Cattaro. This line of desolate mountains, crossed by but few roads and mule-tracks, was the not very effective barrier between mainland Dalmatia and that strange debatable land, the valleys of the Save and the Drave, with their semi-oriental migratory tribes. The aridity of these mountains and of the Dalmatian plateau in general is accounted for by the lack of surface water due to the peculiar “Karst” formation of their limestone rocks, which allows the water to drain off the surface through innumerable pores and fissures and to concentrate in subterranean river-courses, which give rise to such strange and beautiful streams, bursting full-flooded from the foot of some perpendicular crag, often only a mile or so away from the sea, such as the Timavo near Monfalcone on the Triestine Carso, or the Ombla at Gravosa, or the lovely tourmaline waters of the river that rises straight into the sea at Cattaro. This Karst formation of limestone runs all round the head of the Adriatic from the Piave, by Polcenigo, where