with its extremely precipitous outer slopes, and culminating in Mount Miranga, which exceeds 6,500 feet in height. This isolated mass, which, like the Manica uplands, is of granitic formation, is clothed on its upper parts by magnificent forests, presenting a pleasant contrast to the surrounding tracts, which are mostly covered with a stunted growth of brushwood.
River Systems. Marine Currents.
The Sabi (Sabia), the largest watercourse in the Gaza country, forms a very extensive fluvial basin, which stretches from the Matebele highlands north-
eastwards to the Manica Mountains, It has its chief source in the Mashona territory, at an altitude of over 3,000 feet above sea-level, and flows at first in a southerly direction. But after escaping from the uplands, while still at a distance of nearly 200 miles from the ocean, it trends round to the east, and maintains this direction for the rest of its course seawards. During the rainy season the Sabi expands into a potent stream, rushing between banks from one to two miles apart, with too swift a current to be stemmed by river craft. But on the return of the dry season the waters subside rapidly, and then the Sabi flows in a narrow channel not more than 100 feet broad, and even in the centre of the stream scarcely anywhere quite 2 feet deep. Nevertheless it develops a considerable delta, with a shoreline of at. least 60 miles in length, and an area of over 800 square miles intersected by the main branches of the Sabi proper. But this space
