ries in hand
Livingstone had an opportunity for working out several problems, and
instituting comparisons between the phenomena of Inner Africa and the
well-marked changes which go on in other parts of the world. We find
him at this time summing them up as follows:--]

The subject of change of climate from alteration of level has not
received the investigation it deserves. Mr. Darwin saw reason to
believe that very great alterations of altitude, and of course of
climate, had taken place in South America and the islands of the
Pacific; the level of a country above the sea I believe he thought to
be as variable as the winds. A very great alteration of altitude has
also taken place in Africa; this is apparent on the sea-coast of
Angola, and all through the centre of the country, where large rivers
which once flowed southwards and westwards are no longer able to run
in these directions: the general desiccation of the country, as seen
in the beds of large rivers and of enormous lakes, tells the same
tale. Portions of the east coast have sunk, others have risen, even in
the Historic Period. The upper or northern end of the Red Sea has
risen, so that the place of the passage of the children of Israel is
now between forty and fifty miles from Suez, the modern head of the
Gulf. This upheaval, and not the sand from the desert, caused the
disuse of the ancient canal across the Isthmus: it took place since
the Mohamadan conquest of Egypt. The women of the Jewish captivities
were carried past the end of the Red Sea and along the Mediterranean
in ox-waggons, where such cattle would now all perish for want of
water and pasture; in fact, the route to Assyria would have proved
more fatal to captives then than the middle passage has been to
Africans since. It may be true that, _as the desert is now_, it could
not have been traversed by the multitude under Moses--the German
strictures put forth by Dr. Colenso, under the plea of the progress of
science, assume that no alteration has taken place in either desert or
climate--but a scientific examination of the subject would have
ascertained what the country was then when it afforded pasture to
"flocks and herds, and even very much cattle." We know that Eziongeber
was, with its docks, on the seashore, with water in abundance for the
ship-carpenters: it is now far from the head of the Elaic Gulf in a
parched desert. Aden, when visited by the Portuguese Balthazar less
than 300 years ago, was a