KEPOKT OF CHEMICAL, I,AHOKATOUY 
It was evident that the cause of the high figure for suspended matter in the White inHuxofUiue 
Nile on August 4th was influx of water from the Blue Nile, the current of which was 
exceptionally high on that day. An attempt was made to take the sample from a point 
sufficiently far up the river to avoid error from this cause; hut the proportion of sulphates 
and of potassium found shows that there was still a large proportion of Blue Nile water 
present. Omitting, in the calculation, the figure obtained on this date, the monthly 
averages become as follows :— 
BLUE NILE 
Parts pe 
WHITE NILE 
r million 
January ... 
7-'J 
Gl-5 
February ... 
11-G 
55- 7 
March 
5-9 
49-8 
. 
7-8 
49-0 
May . 
28-7 
49-1 
•luue . 
*270* 5 
81-2 
July 
1004-0 
4G-7 
-Angvist ... . 
1904-0 
133-G 
September . 
755*5 
G9-2 
October ... . 
279-G 
•27-r, 
November 
108-8 
CO-2 
December... 
22-0 
48-2 
The above results confirm the observations made in the Second Eeport as to the Suspended 
suspended matter carried hv the White Nile —viz., that this is found in appreciable amount 
, . , . I 1 • • White Nile 
during the entire year, and that the water is never quite clear. As before, the lowest water 
proportion was found in the latter part of September and the first half of October. This is 
obviously accounted for by the fact that during the period of flood of the Blue Nile the flow 
of the White Nile is impeded to such an extent that, south of Khartoum, the river is 
converted into an immense lake. As the result of this slowing-up of the current, the 
heavier particles settle and there is left in suspension only the finest clay-like material. 
The cause of the different behaviours of the two Nile waters, and of their different 
appearance, has already been discussed (Second Eeport, page 210). It was shown that the Conditions 
Blue Nile was able, at certain seasons, to free itself of suspended matter, by reason of its intiuencing 
higher content of calcium and magnesium salts and low proportion of alkali carbonates; suspended*^ 
and that the White Nile, on the contrary, remained “white” or turbid at all seasons as matter in the 
the result, on the one hand, of the presence of less calcium and magnesium salts, and, on the 
other, of a comparatively high proportion of alkali carbonates derived from the decom- White Niles 
position of the vegetable matter of the marshy regions. Even if allowed to stand, 
undisturbed, for a long time. White Nile water usually remains opalescent. 
The above condition of affairs is true only of the White Nile, a considerable distance 
north of the Sudd region. But few samples from the south side of the Sudd region have 
been available, but it appears that the composition of the water above this point is 
appreciably different in several particulars from that of the Sudd region and below. Thus, 
in the series of analyses formerly reported, the sum of the potassium and sodium in the 
water collected at Bor was 37’5 parts per million. By the time the water had reached 
