388 ON THE SETEIA AND 
time of Ptolemy, the Mersey was not open at 
Liverpool, but found its exit over the low lands of 
Cheshire, nor yet can we subscribe to the opinion 
of a writer in the ‘“ Gentleman’s Magazine in 
1796, that the submarine forests at Leasowes and 
at Crosby, were a continuous sub-aerial and living 
one, with the Mersey, a fresh-water stream, run- 
ning through this forest in the days of Ptolemy, 
and therefore unnoticed as an estuary by him; yet 
there is every reason to suppose, that neither the 
impetus nor volume of its fresh or tidal waters was 
near so great as at the present day. The distribu- 
tion of its waters through so many outlets to the 
sea, would keep down its degrading effect in any 
one channel, and preserve the bottoms of all at 
a higher Jevel, than if only one channel, as of late 
centuries, had appropriated the whole force and 
volume of its flowing and ebbing currents. It is, 
still further, very probable, that the Mersey above 
Liverpool had formed a very extensive expanse 
of water, reaching far up beyond Runcorn, and 
up the valley of the Gowy, and not subject to be 
drained off at each ebb of the tide. In fact, it 
might then be considered a sort of inland lake, 
having several communications with the sea, and 
giving great countenance to the present name, 
being derived from its being originally a Mere- 
