MR, HORNER ON THE ALLUVIAL LAND OF EGYPT. 
107 
may have been brought down at irregular intervals, and by unequal increments, they 
afford no data by which we can estimate the rate of increase of the detritus brought 
down by the same river, previously to the foundation of the sea-port town ; nor can 
we discover whether the formation of the land, composed of travelled materials, on 
which the town was built, and which stretches far inland from it, was the operation 
of a brief period of time or of one continued through a long series of ages. 
Egypt affords the earliest authentic evidence of the existence of the human race, 
recorded in works of art ; in its monuments we find the dawn of the historical period 
and of civilization ; and that land alone, of all parts of the world as yet known to us, 
offers an instance of a great geological change that has been in progress throughout 
the whole of the historical period, down to the present day ; and which, we have very 
reasonable grounds for believing, had been going on with the same uniformity for 
ages pridr to that period when our reckoning of historical time begins. I refer to 
the annual inundation of the Nile, and the sediment that falls from its waters on the 
surface of the land it overflows. 
The question of the raising of the valley of Upper Egypt and the formation of the 
Delta by the deposit from the Nile, has been a subject of controversy from the days 
of Herodotus to our own time : there is scarcely a writer on Egypt who does not 
allude to it. Herodotus, who visited Egypt about 455 years before our era, says * 
that ‘Hhe soil of Egypt is a black earth, cracked and friable, as if it had been formed 
by the mud brought down by the Nile from Ethiopia, and which has been accumu- 
lated by its overflowings. The greater part of the land is a present from the Nile, 
as the priests informed me, and it is the conclusion to which I have myself arrived. 
It seemed to me, in truth, that the whole extent of country lying between the moun- 
tains above Memphis was formerly an arm of the sea.” Thus far his conclusions are 
in the main correct ; but he goes farther, conceiving that Lower Egypt was wholly 
formed within historical time ; for he says, “ in proportion as the land extended from 
Upper Egypt by the deposits of the Nile, a part of the inhabitants migrated into 
Lower Egypt.” This latter theory of Herodotus, which an examination of the geo- 
logical features of the country has shown to be erroneous, was even recently adopted 
by the acute and learned Niebuhr, as we learn from the lectures he delivered at 
Bonn, a very short time before his death -I-. 
The theory of Herodotus, supported by Aristotle, Diodorus Siculus, Seneca, 
Strabo, Pliny and Plutarch, was combated in a learned disquisition, in the Memoirs 
of the Academy of Inscriptions and Belles Lettres, by Freret, bearing the date of 
1742 j:, and this memoir was replied to fifty years afterwards by the eminent geolo- 
gist Dolomieu'^. The latter author observes, that the question of the effects of the 
inundations of the Nile on the formation of the Delta had been treated of by the 
* Book ii. 10 and 15. f Alte Geschichte, vol. i, pp. 50. 56. 79. + vol. xvl. p. 333. 
§ Sur la Constitution Physique de I’Egypte, par M. Deodat de Dolomieu, Journal de Physique, 1793, 
tome xi. ii. p. 41. 
Q 2 
