DISCOVERY OF THE PILTDOWN SKULL 297 
west. In the course of time it has cut a valley through 
the Piltdown plateau, until now its bed lies 80 feet below 
the level of the common. It has a journey of fifteen 
miles to make before it reaches the sea at Newhaven. 
In the middle of the Weald, to the north, the land rises 
to form a wooded ridge — the " forest " ridge — forming 
the watershed between the Ouse and the Medway, a 
Fk;. 96. — Sketch of the district drained by the Sussex Ouse, showing the area 
over which Mr Dawson found peculiar tabular flints and traces of ancient 
gravel dejiosits (after Mr Dawson's illustration). 
tributary of the Thames. The " forest " ridge hides 
from view the North Downs, which rise sharply up and 
separate the Weald from the Thames valley. 
Having thus accompanied Mr Dawson into the Weald, 
he himself will take up the narrative, as told in a com- 
munication to the Geological Society of London.^ 
• From the (luarterly Journal of the Geoloi(ical Society, March 191 3, 
vol. Ixi.x. p. 117. 
