"In Truth, Therefore, The Inner Portion Of Southern Africa Is, In This
Respect, As Far As I Know, Geologically Unique In The Long Conservation
Of Ancient Terrestrial Conditions.
This inference is further supported
by the concomitant absence, throughout the larger portion of all this
vast area, i.
E. south of the Equator, of any of those volcanic rocks
which are so often associated with oscillations of the terra firma
["Although Kilimandjaro is to a great extent igneous and volcanic, there
is nothing to prove it has been in activity during the historic era."]
"With the exception of the true volcanic hills of the Cameroons recently
described by Burton, on the west coast, a little to the north of the
Equator, and which possibly may advance southwards towards the Gaboon
country, nothing is known of the presence of any similar foci of
sub-aerial eruption all round the coasts of Africa south of the Equator.
If the elements for the production of them had existed, the coast-line
is precisely that on which we should expect to find such volcanic vents,
if we judge by the analogy of all volcanic regions where the habitual
igneous eruptions are not distant from the sea, or from great internal
masses of water. The absence, then, both on the coasts and in the
interior, of any eruptive rocks which can have been thrown up under the
atmosphere since the period when the tertiary rocks began to be
accumulated, is in concurrence with all the physical data as yet got
together.
Enter page number
PreviousNext
Page 629 of 662
Words from 169492 to 169746
of 178435
