Page:Africa by Élisée Reclus, Volume 4.djvu/321

THE ZAMIJICSK DELTA 2M inundations. Of all tlio branches tho most copious is the eastern Lu-Ebo, tho true Zumbosc, although shipping moHt usually prefers the Inhamissongo, whore the depth ranges from 10 to 23 or 24 feet, according to the season and the tides. But all the channels are frequently modified by storms and floodH, und both on the north and the M)uth side of the delta are seen old watercourses which were formerly mouths of tho erratic river, but are now merely winding streams or backwaters, cither completely separated from tlie Zambcsc or only temporarily connected with it during tho Hoods. Scu-going vessels can easily ascend the Ix)wer Zumbese an far as the foot of Mount Mirambula, sailing before the east wind which mostly prevails in this region. Geologically the delta is far more extensive than it appears at present. It may be said to Ix^gin almost immediately below the Shire confluence, where the channels of backwaters and false rivers, survivals of an ancient current, and still flooded during tho inundations, are seen to diverge gradually from the mainstream in the direction of the east. Here they effect a junction with the sluggish current of tho Rio Muto, which formerly communicated with the Quelimune estuary, but which is now completely obstructed by alluvial deposits and aquatic plants. Hence the necessity of seeking another channel or outlet for the riverain craft, which was found somewhat lower down tho Zambese at a portage leading to the Barabuauda, better known as the Kwa-Kwa (Quu-Qua), or " liiver of Forced Labour," because the natives are compelled to deepen or keep it ojHjn by dredging. This watercourse winds in the direction of Quelimane, which seaport it reaches after a course of over 70 miles. For more than half of this distance above the port it is navigable for steamers drawing G or 7 feet of water, and the whole distance for light craft. During the annual inundations of the Zambese, its banks are completely flooded, ,and tho mainstream thus becomes united with the Quelimane River through an intricale network of marshy depressions. The river has moreover recently shifted its bed, and now reaches the coast some 6 miles farther north, that is, so much nearer to its periodical Quelimane branch. The abandoned channel is still visible, now transformed to a circular lagoon. The sjime erosive action is still progressing northwards, and tho " African Lakes Company " has already had to forsake a building which till recently stood about half a mile from the bank, and erect another some considerable distance farther to the north. Should this northward tendency be continued much longer, the Zambese will effect a permanent junction with the Kwa-Kwa, and tho original delta will be restored to its full dimensions. In any case a navigable communication might easily be established between the Zambese and Quelimane by cutting a canal through the intervening low-lying portage. Southwards also tho Zambese communicates during the inundations with several streams traversing the Gaza territory. Here the junction is effected by a lagoon belonging to the Zangwe tributary to its lower course, and by a succession of channels and backwaters extending as fur as the River Pungwe, on the Sofala coast.