BELISAMA OF PTOLEMY. 389 
sea or Lake sea, given to it by the Frisians in the 
time of the Romans; as I have, in a former paper 
read before the Society, endeavoured to show. 
Besides the ancient name of Liverpool being 
written Litherpool, which signifies a sluggish 
or still pool, denotes that the waters at this now 
busy emporium of navigation and trade, did not in 
those remote days, exhibit the tidal velocity and 
force which they now so remarkably do. 
In conclusion, I fear I have detained the So- 
ciety too long on the foregcing points of ancient 
and modern hydrography, and on the comparative 
observations and opinions of the several writers 
mentioned, but I have thought the subject, in 
some manner, worthy of a little critical revision, 
both in a historical and geographical view. 
The lapse of time has produced great changes 
on the surface of the earth, and very notably on 
the relative boundaries of land and water, and it 
is curious to compare the existing geography and 
geology of many coasts, estuaries, and courses of 
rivers, with the records of ancient history. Now, 
these are often very indefinite and obscure, but 
they are, on that account, no less worthy of study, 
nor less exciting in interest, so far as they give a 
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