176 Scientific Proceedings, Royal Dublin Society. 
sider that a process of subsidence has been taking place, submerg- 
ing not only bogs, but the work of man’s hands, as on the Aran 
Isles, surely it might happen that far less than 250 years of cease- 
less surge is capable of removing more clay and rock than this 
little speck upon the waters must have had. It is hopeless to look 
for information to English sources; the navigators of their ships 
appear never to have sailed our western waters, and their maps, 
so far as I can ascertain, are unreliable; indeed, you may look 
in the present day over numerous English maps and fail to 
discover Rockall itself, So far as their evidence goes it would be 
conclusive that there was no such place in existence. 
TITLE OF Map, PLATE 9. 
Carte de Des Isles et Costes maritimes de L, EUROPE, ot lon 
voist La Routte et navigation des hollandois at nord d’irlande et 
d’escosse durant La querelle des anglois par L’ocean germaniyue. 
