In the Roman plays the Tiber is repeatedly noticed. The Thames occurs in Merry Wives of Windsor, and others. And in the Egyptian scenes of Antony and Cleopatra, the Nile is several times introduced.
"Master Brook [says Falstaff], I will be thrown into Etna, as I have been into Thames, ere I will leave her thus."
Antony exclaims:
"Let Rome in Tiber melt!"
while Cleopatra gives utterance to the same sentiment:
"Melt Egypt into Nile! And kindly creatures
Turn all to serpents!"
In the last two passages it may be observed, that the hyperbolical treatment of the two rivers bears some analogy to that of the eisell; and it may also be pointed out, that although one of your correspondents has rashly maintained that the word cannot mean a river because the definite article is omitted before it, Thames, Tiber, and Nile here occur without. Upon the whole it must appear that there is some reason for adopting the motto:
"Flow on, thou shining river."
T.