Surveys in British Central Africa were taken up in 1894; a survey of Lake Nyasa, by Lieut.
In December 1901 the mullah was, however, once more raiding in the neighbourhood of Burao, and in May Wars with 1902 Colonel Swayne led another expedition against the Mullah him, the Somali levies being strengthened by the 2nd Mahomme dKing's African Rifles, consisting of Yaos from Nyasa- Abdullah.
The stream of supply came mainly from the southern Nyasa districts by three or four routes to Ibo, Mozambique, Angoche and Quilimane.
It was believed in 1862 that about 19,000 passed every year from the Nyasa regions to Zanzibar, whence large supplies were drawn for the markets of Arabia and Persia up to 1873.
It is said that, whereas io,000 slaves formerly passed the southern end of the Nyasa every year, in 1876 not more than 38 were known to have been conveyed by that route.
After the establishment of the Zulu military ascendancy early in the 19th century various Zulu hordes successively invaded and overran a great part of east-central Africa, as far as and even beyond the Lake Nyasa district.
Above the sea, and occupies the southern end of the great central rift-valley, which terminates suddenly at its southern point, the line of depression being represented farther south by the more easterly trough of Lakes Nyasa and Rukwa, from which Tanganyika is separated by the Fipa plateau, composed of old granitoid rocks; though even here traces of old valley-walls are said by Dr Kohlschiitter to exist.
The greater part of the trade with Tanganyika is done by the African Lakes Corporation by the Shire-Nyasa route, but the Germans have opened up overland routes from Dar-es-Salaam.
Across the plateau between Lakes Tanganyika and Nyasa, in its southern section following the course of the river Songwe.
Thence it goes down the middle of Nyasa as far as 11 ° 30' S.
As already indicated, the southern half of Victoria Nyanza and the eastern shores, in whole or in part, of Lakes Kivu, Tanganyika and Nyasa, are in German territory.
Lake Rukwa north-west of Nyasa is presumably only the remnant of a much larger lake.
Of inland river systems there are four - one draining to Victoria Nyanza, another to Tanganyika, third to Nyasa and a fourth to Rukwa.
Of the streams entering Nyasa the Songwe has been mentioned.
The Ruhuhu, which enters Nyasa in 10° 30' S., and its tributaries drain a considerable area west of 36° E.
In the vicinity of Lakes Nyasa and Tanganyika, sandstones and shales of Lower Karroo age and yielding seams of coal are considered to owe their position and preservation to being let down by rift faults into hollows of the crystalline rocks.
The rift-valley faults continue down the depression, marked by numerous volcanoes, in the region of the Natron Lake and Lake Manyara; while the steep walls of the deep depression of Tanganyika and Nyasa represent the western rift system at its maximum development..
They are spread over the central plains, and have for neighbours on the south-east, between Nyasa and the Rufiji, the warlike Wahehe.
The Wangoni (Angoni), a branch of the Ama-Zulu, are widely spread over the central and Nyasa regions.
Wiedhafen is on the east side of Nyasa at the mouth of the Ruhuhu, and is the terminus of the caravan route from Kilwa.
Good roads for foot traffic have been made from the seaports to the trading stations on Lakes Nyasa, Tanganyika and Victoria.
Though the revolt spread over a very large area, the chief centre of disturbance was the region between Nyasa and the coast at Kilwa and Lindi.
Besides a number of settlers a Roman Catholic bishop and a party of four missionaries and nuns were murdered in the Kilwa hinterland, while nearer Nyasa the warlike Wangoni held possession of the country.
The restless Arabs of Zanzibar had since 1857 steadily advanced Zanzibar influence to Tanganyika, Nyasa, and even through the Masai countries to the north-east coast of Victoria Nyanza and the " back door " of Uganda.
- Missions: Algeria, Sahara, Nyasa, Victoria.
Short of Lake Nyasa with its 350 m.
The disablement of the only German boat on Lake Nyasa by Comm.
Suess as far south as Lake Nyasa.'
Of Lake Nyasa, cut by 35° 20' E., and lying between 15° and 15° 35' S.
Most of the year 1859 was spent in the exploration of the river Shire and Lake Nyasa, which was discovered in September; and during a great part of the year 1860 Livingstone was engaged in fulfilling his promise to take such of the Makololo home as cared to go.
The two main objects of the expedition were the suppression of slavery by means of civilizing influences, and the ascertainment of the watershed in the region between Nyasa and Tanganyika.
Rounding the south end of Lake Nyasa, Livingstone struck in a north-northwest direction for the south end of Lake Tanganyika, over country much of which had not previously been explored.
Towards the south the two lines converge and give place to one great valley (occupied by Lake Nyasa), the southern part of which is less distinctly due to rifting and subsidence than the rest of the system.
All the largest tributaries, including the Shire, the outflow of Lake Nyasa, flow down the southern slopes of the band of high ground which stretches across the continent in to 12° S.
As a rule the lakes which occupy portions of the great rift-valleys have steep sides and are very deep. This is the case with the two largest of the type, Tanganyika and Nyasa, the latter of which has depths of 430 fathoms. Others, however, are shallow, and hardly reach the steep sides of the valleys in the dry season.
Such are Lake Rukwa, in a subsidiary depression north of Nyasa, and Eiassi and Manyara in the system of the eastern rift-valley.
The lip-plug is found in the eastern area, especially among the Nyasa tribes, but not in the south.