1893. DESERT CONDITIONS IN BRITAIN. 369 



consequences of the existence of a cold dry epoch Hke that indicated 

 by the fossils. In the first place, with a clear sky the winter must 

 have been much colder, and all pervious strata would become frozen 

 and impervious to a considerable depth. Any rain falling before the 

 thick frozen layer had melted could not sink in, but would im- 

 mediately drain off the surface, carrying away with it a thin layer of 

 rock shattered by the frost. Thus, the chalk Downs, which now yield 

 perennial springs, even after a drought such as that of the past 

 summer, would then yield no springs, for the rain could not penetrate. 

 When the surface was frozen, the heaviest fall of rain would be 

 entirely thrown off these steep slopes in a few hours, and the Downs 

 would become channelled by ravines containing impersistent torrents, 

 such as we now only associate with mountain regions where the rocks 

 are impervious. As soon as the torrents reached flatter open country, 

 the material brought down would be deposited in fan-shaped deltas, 

 like that on which Chichester is built. 



Implements made by man are not uncommonly to be met with 

 beneath such gravel deposits, and these discoveries are often, but to 

 me unaccountably, taken to prove the former existence of rivers at 

 spots now high up the slopes of hills, or even near the highest points 

 of nearly level plateaux. From the occurrence of stratified gravels 

 above the implements in such situations, it is further argued that since 

 Palaeolithic times deep valleys have been cut out, and what were 

 formerly the alluvial flats, have now become outliers of implement-bear- 

 ing gravel capping isolated hills. Many writers even reason as though 

 Palaeolithic man were an amphibious animal, unable to live far from 

 a river, and absolutely proving from the abundance of his weapons at 

 certain spots, that a river must once have existed in the immediate 

 neighbourhood. If such were the case, Palaeolithic man must have 

 been very different from existing savage races of the arctic and 

 temperate regions. An overwhelming desire for an abundant supply 

 of water is not a marked characteristic of these, and, as a rule, a 

 small quantity for drinking purposes is all that they require. We 

 have evidence that Palaeolithic man hunted the big game that was 

 then so plentiful ; but we have no evidence in this country that he 

 was much of a fisherman. 



The conditions under which the implements are found, often 

 scattered over deeply-buried ancient land-surfaces, and associated 

 with hearths and other remains, which prove that on that spot was 

 the site of an ancient settlement,' are to me more suggestive of 

 sudden flood action than of ordinary rivers. Is it not possible that 

 Palaeolithic man may have lived on the existing hills and plateaux, 

 and that the gravel beneath which his remains are buried is merely 

 a local flood gravel deposited in any hollow over the frozen slopes, 

 and not necessarily proving the existence of any river at such heights ? 



1 See Worthington G. Smith, ref. no. 6. 



2B 



