28 THE ANTIQUITY OF MAN 
There is no feature of his head which marks him off 
from his successors of to-day. Like the people of 
Coldrum, he has a skull of the river-bed type. In brain 
capacity he is the equal of the average man of to-day, 
his capacity being just under 1500 c.c. In height he 
was about the same as the Coldrum men — about 5 
feet 4 inches (i'630 m.). He has the same flattening 
of the thigh and leg bones as is to be seen in them. The 
skeleton lay 3 feet below the old land surface, laid to 
rest there, we presume, by the hands of his comrades. 
Neither he nor they could ever have dreamed of the day 
when great steamers would sail over the land which was 
their home. Such worked flints and animal remains as 
have been found, indicate that the old land surface — the 
submerged-forest surface — was inhabited at an early part 
of the Neolithic period. 
Can we form any reasonable estimate of the centuries 
which have passed since the Tilbury man lived ? Only 
three years ago, when I last discussed the discovery at 
Tilbury,^ I was impressed by the generally accepted 
opinion that there was no definite evidence of submergence 
in the lower valley of the Thames since the Roman occupa- 
tion. Apparently, the land had been stationary during 
the last two thousand years. It therefore seemed to me, 
then, that submergence must be a slow process. If we 
supposed it to take place at the rate of 2 feet in a thousand 
years, it would take quite fifteen thousand years for the land 
surface which carried the submerged forest to sink, as at 
Tilbury, over 30 feet beneath the present level of the marsh. 
Subsidence evidently occurs at a more rapid pace than I 
had estimated. Mr Spurrell noted, when the Tilbury 
docks were being cut, that an old land surface, " strewn 
with Roman refuse," lay about 7 feet below the present 
surface level. At first sight that observation seems to 
show that the land surface at Tilbury had sunk 7 feet 
since the Roman occupation. Mr Clement Reid, whose 
opinion must carry weight in such a matter, thinks that 
much of this subsidence is only apparent, and is really due 
' Ancient Types of Man, Harper Brothers, 191 1. 
