21 
re-emergence, took “in round numbers 180,000 years for its 
completion.” 
Well does the veteran philosopher add : — “ I am aware that 
it may be objected that the average rate here proposed is a 
purely arbitrary and conjectural one.”* 
Dr. Andrews appears to show, by careful observations, that the 
present surface-land of North America rose out of the waters of 
the glacial period between 5,500 and 7,500 years ago. This 
appears to limit within these bounds the possible duration of the 
human period in North America. Dr. Dawson says there are 
other lines of evidence which would reduce the residence of man 
in America to a much shorter time.-)- From a communication 
to “Nature,” of January 14, 1875, we gather that the dis- 
tinction between palaeolithic and neolithic obtains in implements 
imbedded in the soil there — the former being always rough 
and more deeply buried. But we also infer that both belong 
to one type of people, and that the superiority of the latter is 
the result of progressive improvement. 
The wearing away of the land to the south of the Hampshire 
coast, partly in soft beds and partly in chalk, would require, it 
is said, far more than ten thousand years. But why go into such a 
calculation at all, inasmuch as the hypothesis of gradual uniform 
erosion is wholly inadmissible. Mr. Evans, placing his spec- 
tator on the edge of the Bournemouth cliff, and bidding him 
gaze over the waste of waters in quest of the lost Atlantis, may 
as well accept the ancient tradition of its sudden submergence, 
confirmed as it is by the appearance of the cliffs. The gazer, on 
any other supposition, could have beheld no appreciable change, 
and there would have been nothing remarkable in the prospect, 
however long he might have continued at his post. With 
regard to the antiquity of the implements, Mr. Evans says : — 
“ With our present amount of knowledge, it is hopeless to 
attempt its determination with anything like precision.”! This 
does not exclude hypotheses, but it reduces it to mere working 
suggestion. What, then, is the value of Mr. Evans’s argument 
for a long period between the change from palaeolithic to 
neolithic? He says: “It can hardly have been the work of a 
few years, or even of a few centuries.” Granted ; but when it 
is evident that the change did not take place from ordinary 
slow causes, but was necessitated by sudden alterations, a 
period of one thousand years will amply suffice. If Mr. Tylor 
* Since these observations were written, and on the 22nd of the present 
month, this distinguished philosopher has passed away. 
t Dawson, Earth and Man, p. 295. 1 Ibid., p. 617. 
