418 Geographical Notices. 
may it then be fairly considered as the main source of the great 
river; the more so when we see that its southern end is farther 
to the south, or more remote from the embouchure, than any 
other portion of the Nilotic water-parting.* On the other hand, 
the high mountains which flank the great stream on the east, and 
probably supply it with some of its waters, may by other geog- 
raphers be rather viewed as the main and original source. These 
are the only remaining portions of the great problem which have 
to be worked out—a problem which it has been the desideratum 
of all ages to unravel, and one which, according to Lucan, made 
Julius Cesar exclaim, that to gain this knowledge he would even 
abandon the civil wart—a problem which Nero sent his centu- 
rions to determine, and which, by the last discovery of Captain 
Speke, seems certainly now to approach nearly to a satisfactory 
solution.” 
WARREN’S MEMOIR TO ACCOMPANY A Map oF THE WESTERN 
Territory or U.S.—We have already referred to the admirable 
map by Lieut. G. K. Warren, U.S. Topog. Eng., prepared to 
illustrate the result of the various expeditions of the government 
to the teritory west of the Mississippi river.t We have now 
received a volume from the pen of the same officer, illustrative 
of the map. It is printed from the advance sheets of the eleventh 
volume of the Pacific Rail Road Surveys. This memoir is not 
“a 
exploring expeditions in the West since 1800 
The firs 
ft. 
The second period, from 1832 to 1844, includes the exploration 
of Bonneville, the early discoveries in Great Salt basin, Nicollet's 
hydrographical survey of the upper Mississippi, the beginning of 
rémont’s travels, and other reports and maps of army officers, 
the topographical engineers. : 
The third chapter is devoted to more than twenty expeditions, 
of greater or less importance undertaken between 1848 and 1852, 
almost exclusively under the patronage of the U.S. Government. 
rse 0 
this feature, as well as on the parallelism of its course to the great N. and S. de- 
pression of the Red Sea, on the fertilizing powers of its waters, and on the . 
icity of its flood, the reader will do well to consult the article “ Mediterranean Sea, 
‘ Review, vol. cvi., which i of our accomplished associate 
Sir Henry Holland. 
eS ¢ “Spes sit mihi certa videndi 
Niliacos fontes bellum civile relinquam.”—Lucan, Book 10. 
(As quoted by Mr. M’ 
goo Beebe pane RO 
