136 Trihutnries of (he Sobat.

Klior Makeir.

Trtbiitaries on left bank. NiRol or Aluro.

Pibor.

Width.

Navigability.

Discharsre.

Rout«.

Inbabitantx.

Trade goodii.

Anuakx. Tributaries of Pilxir. The -Agwei (tiwynn), or Neubari (Austin), or Ruzi II (WellbyX or AHjouaro (Faivre).

The Khor Garre, which forms the boundary between the Sudan and Abyssinia in these regions, brings down a large quantity of water in flood time from the Galla hills. In the dry season water stands in pools in its bed.

For the first 20 miles from its mouth this khor is inhabited by or belongs to the Nuers, then for a few miles by the Anuaks or Yambos, whose district is called Chai, and higher up by Burun.

About 8 miles east of the Pibor junction, Khor Makeir comes in on the right bank. This, near its mouth, is deep, with a sandy bed 30 yards wide. It has not been explored, but is believed by some to be the mouth of the Sonka, in which case it has its origin near Jebel Sonka in the Galla hills south of Kirin. Others say it is only a spill from the Baro.

The River Nigol (Nuer) or Aluro (Anuak) enters the Baro about 17 miles below Itang. It appears to have its origin on the Abyssinian plateau, and for some 25 miles before its junction with the Baro it flows parallel to that river, at a distance often of little more than a mile. In flood time it is a most formidable obstacle, as it forms large areas of swamp. Its entry into the Baro, near the border between Anuak and Nuer territory, is a very insignificant one, and barely discernible, as it spills out into a large swamp, near the village of Methok, before it reaches the actual river, and apparently the water gradually finds its way into the river through a thick forest-growth of trees by two small channels only a few feet wide. From the point where the Adura takes off from the Baro, the banks of the latter river are thickly wooded with sycamore and other trees as far as the eastern boundary of Nuer territory.

The Pibor flows generally from south to north, and enters the Sobat river at a point about 25 miles above Nasser and about 200 miles from its (Sobat) mouth. It is by far the most important tributary of the Sobat. The Pibor was found (June, 1903) to be blocked by sudd immediately above the Akobo junction, and so its upper waters remained unexplored until Septembar, 1904.* The greenish colour of its water would lead one to suppose that it receives its supply from vast marshes in the plain between the Akobo and the Nile, rather than from the Abyssinian plateau. f The banks of the lower Pibor are, as a rule, swampy, especially at the season when the river is fullest. The adjoining country is flat and covered with grass, with but few trees, though, south of Koratong, the banks are firm and dry, and trees become general, especially on the right bank.

The waterway of the Pibor in its lower reaches is exceedingly narrow, a steamer frequently touches the reeds of either bank simultaneously. About 40 miles from its mouth, however, it widens to from 40 to 100 yards.

The Pibor river has not (1903) been navigated by steamer in the months of February, March, and April, during which period it appears probable navigation would be difficult, if not impossible. During the rest of the year the average depth of water is at least 10 feet.

The discharge at the mouth of the Pibor, calculated by Captain H. H. Wilson in October, 1901, worked out at roughly 13,-500 gallons per second. The width of the river here being about 80 yards, of which about 30 yards was blocked by sudd. The maximum depth was nearly 30 feet, and the current rather more than 1 mile an hour.

There is a route over comparatively dry country from Nasser to Waratong (45 miles approximately) The inhabitants of the lower Pibor are Nuers, whose principal villages are a group at Koratong and another at Kur, both situated on the left bank. These appear to be the permanent homes of this section (Sheikh Jok's) of Nuers, but in the dry season they occupy other villages both north and south along the Pibor, the most important of which is Bil (right bank) near the junction of the Gelo River ; during this season Nuers from other districts visit the Pibor for fishing.

The Nuers of the Pibor do not differ in any essential degree from those of the Sobat and Baro, and are just as disinclined as their kinsmen to recognise the advantages of civilisation.

Dura was purchased from the late Sheikh Yowe's (now Jok's) people for small white and dark blue beads, not much larger than a pin's head. A string sufficiently large to pass over the head on to the neck purchased from 1 pound to li pounds of unground grain. A spear length of brass wire, about 9 feet in length, purchased a goat of average size. Coloured fancy cloth will soon be in much request.

A few Anuaks are found on the right bank, these are more or less subject to the Nuers. Their Sheikh is Okwai.

The "Agwei" River joins the Pibor about 17 miles south of the Akobo junction. It was found by the Faivre Expedition (1898), by whom it was named the Adjouaro, to rise in the Southern Boma hills and to flow northwards to within a few miles of th'j left bank of the Akobo, and then bending westwards to flow parallel with that river to the Pibor, or, as they called it, the Adjouba (Agibba ?). The Agwei was also heard of by Major Austin when marching through Boma ; it was described as a big river and was named by him the Neubari. It is also probably the same as WeUby's Ruzi II.

In September, 1901, Major Gwynn explored this branch of the Pibor in a steam-launch for 55 miles from its mouth, when further progress was arrested by heavy sudd. He describes it as a fine stream flowing between welldefined banks, averaging 3 feet above the level of the river in flood and 60 to 80 yards apart. In places, however, it had overflown its banks and flooded the adjoining country to a considerable depth. The average width of * For description of Upper Pibor, vide ]x lijl. t In June, 1904, the {iJBcharge at its mouth was observed to be a dirty-wliite colour.