Page:EB1911 - Volume 05.djvu/241

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228  
CAPE COLONY
[CLIMATE

the waters which descend from the famous Hex River Pass. The Breede thence follows the line of the Langeberg mountains as far as Swellendam, where it turns south, and traversing the coast plain, reaches the sea in St Sebastian Bay. From its mouth the river is navigable by small vessels for from 30 to 40 m. East of the Breede the following rivers, all having their rise on the inner mountain chain, are passed in the order named:—Gouritz (200 m.),[1] Gamtoos (290 m.), Sunday (190 m.), Great Salt (230 m.), Kei (150 m.), Bashee (90 m.) and Umzimvuba or St John’s (140 m.).

The Gouritz is formed by the junction of two streams, the Gamka and the Olifants. The Gamka rises in the Nieuwveld not far from Beaufort West, traverses the Great Karroo from north to south, and forces a passage through the Zwarteberg. Crossing the Little Karroo, it is joined from the east by the Olifants (115 m.), a stream which rises in the Great Karroo, being known in its upper course as the Traka, and pierces the Zwarteberg near its eastern end. Thence it flows west across the Little Karroo past Oudtshoorn to its junction with the Gamka. The united stream, which takes the name of Gouritz, flows south, and receives from the west, a few miles above the point where it breaks through the coast range, a tributary (125 m.) bearing the common name Groote, but known in its upper course as the Buffels. Its headwaters are in the Komsberg. The Touws (90 m.), which rises in the Great Karroo not far from the sources of the Hex river, is a tributary of the Groote river. Below the Groote the Gouritz receives no important tributaries and enters the Indian Ocean at a point 20 m. south-west of Mossel Bay.

The Gamtoos is also formed by the junction of two streams, the Kouga, an unimportant river which rises in the coast hills, and the Groote river. This, the Groote river of Cape Colony, has its rise in the Nieuwveld near Nels Poort, being known in its upper course as the Salt river. Flowing south-east, it is joined by the Kariega on the left, and breaking through the escarpment of the Great Karroo, on the lower level changes its name to the Groote, the hills which overhang it to the north-east being known as Groote River Heights. Bending south, the Groote river passes through the coast chain by Cockscomb mountain, and being joined by the Kouga, flows on as the Gamtoos to the sea at St Francis Bay.

Sunday river does not, like so many of the Cape streams, change its name on passing from the Great to the Little Karroo and again on reaching the coast plain. It rises in the Sneeuwberg north-west of Graaff Reinet, flows south-east through one of the most fertile districts of the Great Karroo, which it pierces at the western end of the Zuurberg (of the coast chain), and reaches the ocean in Algoa Bay.

Great Salt river is formed by the junction of the Kat with the Great Fish river, which is the main stream. Several small streams rising in the Zuurberg (of the inner chain) unite to form the Great Fish river which passes through Cradock, and crossing the Karroo, changes its general direction from south to east, and is joined by the Kooner (or Koonap) and Kat, both of which rise in the Winterberg. Thence, as the Great Salt river, it winds south to the sea. Great Fish river is distinguished for the sudden and great rise of its waters after heavy rain and for its exceedingly sinuous course. Thus near Cookhouse railway station it makes an almost circular bend of 20 m., the ends being scarcely 2 m. apart, in which distance it falls 200 ft. Although, like the other streams which cross the Karroo, the river is sometimes dry in its upper course, it has an estimated annual discharge of 51,724,000,000 cubic ft.

The head-streams of the Kei, often called the Great Kei, rise in the Stormberg, and the river, which resembles the Great Fish in its many twists, flows in a general south-east direction through mountainous country until it reaches the coast plain. Its mouth is 40 m. in a direct line north-east of East London. In the history of the Cape the Kei plays an important part as long marking the boundary between the colony and the independent Kaffir tribes. (For the Umzimvuba and other Transkei rivers see Kaffraria.)

Of the rivers rising in the coast chain the Knysna (30 m.), Kowie (40 m.), Keiskama (75 m.) and Buffalo (45 m.) may be mentioned. The Knysna rises in the Uiteniquas hills and is of importance as a feeder of the lagoon or estuary of the same name, one of the few good harbours on the coast. The banks of the Knysna are very picturesque. Kowie river, which rises in the Zuurberg mountains near Graham’s Town, is also noted for the beauty of its banks. At its mouth is Port Alfred. The water over the bar permits the entrance of vessels of 10 to 12 ft. draught. The Buffalo river rises in the hilly country north of King William’s Town, past which it flows. At the mouth of the river, where the scenery is very fine, is East London, third in importance of the ports of Cape Colony.

The frequency of “fontein” among the place names of the colony bears evidence of the number of springs in the country. They are often found on the flat-topped hills which dot the Karroo. Besides the ordinary springs, mineral and thermal springs are found in several places.

Lakes and Caves.—Cape Colony does not possess any lakes properly so called. There are, however, numerous natural basins which, filled after heavy rain, rapidly dry up, leaving an incrustation of salt on the ground, whence their name of salt pans. The largest, Commissioner’s Salt Pan, in the arid north-west district, is 18 to 20 m. in circumference. Besides these pans there are in the interior plateaus many shallow pools or vleis whose extent varies according to the dryness or moisture of the climate. West of Knysna, and separated from the seashore by a sandbank only, are a series of five vleis, turned in flood times into one sheet of water and sending occasional spills to the ocean. These vleis are known collectively as “the lakes.” In the Zwarteberg of the central chain are the Cango Caves, a remarkable series of caverns containing many thousand of stalactites and stalagmites. These caves, distant 20 m. from Oudtshoorn, have been formed in a dolomite limestone bed about 800 ft. thick. There are over 120 separate chambers, the caverns extending nearly a mile in a straight line.

Climate.—The climate of Cape Colony is noted for its healthiness. Its chief characteristics are the dryness and clearness of the atmosphere and the considerable daily range in temperature; whilst nevertheless the extremes of heat and cold are rarely encountered. The mean annual temperature over the greater part of the country is under 65° F. The chief agents in determining the climate are the vast masses of water in the southern hemisphere and the elevation of the land. The large extent of ocean is primarily responsible for the lower temperature of the air in places south of the tropics compared with that experienced in countries in the same latitude north of the equator. Thus Cape Town, about 34° S., has a mean temperature, 63° F., which corresponds with that of the French and Italian Riviera, in 41° to 43° N. For the dryness of the atmosphere the elevation of the country is responsible. The east and south-east winds, which contain most moisture, dissipate their strength against the Drakensberg and other mountain ranges which guard the interior. Thus while the coast-lands, especially in the south-east, enjoy an ample rainfall, the winds as they advance west and north contain less and less moisture, so that over the larger part of the country drought is common and severe. Along the valley of the lower Orange rain does not fall for years together. The drought is increased in intensity by the occasional hot dry wind from the desert region in the north, though this wind is usually followed by violent thunderstorms.

Whilst the general characteristics of the climate are as here outlined, in a country of so large an area as Cape Colony there are many variations in different districts. In the coast-lands the daily range of the thermometer is less marked than in the interior and the humidity of the atmosphere is much greater. Nevertheless, the west coast north of the Olifants river is practically rainless and there is great difference between day and night

  1. The distances given after the names of rivers indicate the length of the river valleys, including those of the main upper branch. In nearly all instances the rivers, owing to their sinuous course, are much longer.