THE PREHISTORIC EAST 175 



some subsidence in the delta in consequence of the 

 weight of sediment, and estimating the average rate 

 of deposition at one-fifteenth of an inch per annum, 

 which is as low an amount as can probably be 

 assumed, we shall have numbers ranging from 5,300 

 to about 7,000 years for the lapse of time since the 

 delta was a bay of the Mediterranean. 



It is true that the recent borings in the delta, 

 under the officers of the British Engineers, have 

 shown a great depth in some places without reaching 

 the original bottom of the old bay. Some geologists 

 have accordingly inferred from this a much greater 

 age for the deposit than that above stated, 1 and in 

 this they are in one respect justified ; but they have 

 to bear in mind that only the upper part of the 

 material belongs to the modern period. A vast thick- 

 ness is due to the pleistocene and pliocene ages, when 

 the Nile was cutting out its valley and depositing the 

 excavated material in the sea at its mouth. A careful 

 examination of the borings proves by their composi- 

 tion that this is actually the case. 2 Geologists who 

 have been guided by these facts in their estimates of 

 time have been taunted as affirming that a great 

 diluvial catastrophe occurred while quiet government 

 and civilised life were going on in Egypt. The 

 evidence for this early date of Egyptian colonisation 

 of the Nile valley is, as everyone knows, doubtful, 



1 Judid, Report to Royal Society, 1885. 



2 Modern Science in Bible Lands, where evidence of similar dates 

 fa other countries is stated. 



