THE AVON AND ITS GRAVELS 
235 
tliat there was a time when our local hills and valleys were 
coated in an ice sheet, as were, we know, those of the 
North and Midland counties. Indeed, Charles Moore 
always held this opinion from other indications which he 
had observed.” The “ other indications ” seem to refer 
to the fact that the soft Liassic clay is furrowed where it is 
overlain by the gravels. 
It is never wise to postulate an agency which usually 
does its work on a vast scale and leaves its evidence written 
large, to account for small and local phenomena when 
evidence on a large scale is wanting. The large blocks 
are, I think, evidence of the great volume of water which 
flowed in the channel in those times. The work of the 
Avon as an excavator is now almost done ; but when it 
flowed one hundred feet above the present bed and was in 
flood, the amount of descent, together with the great mass 
of water which rushed along, would probably be sufficient 
to account for the presence of these blocks in its bed. 
In these low level gravels mammalian remains are abun- 
dant. They include teeth and bones of many Quaternary 
forms. In the two highest gravel pits mentioned teeth and 
bones are generally found resting on the Liassic clay. In 
some cases one half of the fossil retains the bluish tint of 
the material on which it rests, while the other side takes on 
the yellowish tint of the gravels. In the lowest gravels 
the fossils are generally found mixed up with the 
pebbles. 
The palaeontology of the Avon gravels should, I think, 
form the subject of a separate paper, but as the evidence 
the fossils yield as to the age of the Avon is important, 
it is briefly mentioned here. The following are the 
principal fossils found : — 
I. The Mammoth (Elephas primigenius) . The remains of 
this species of elephant are fairly abundant, and include 
molar and incisor teeth (tusks), and bones. 
