ence of these lines on
London, which is as marked a feature of the map of Roman Britain as it
is of our railway maps now, must have already been noticeable. And the
only possible reason for this must be found in the fact that already
London was a noted passage over the Thames. That an island in
mid-stream was the original _raison d'etre_ of London Bridge is
apparent from the mass of buildings which is shown in every ancient
picture of that structure clustering between the two central spans.
This island must have been a very striking feature in primaeval days,
coming, as it did, miles below any other eyot on the river, and
must always have suggested and furnished a comparatively easy
crossing-place. Possibly even a bridge of some sort may have existed
in 54 B.C.; anyhow this crossing would have been alike the objective
of the invading, and the _point d'appui_ of the defending army. And
the line both of the Roman advance and of the British retreat would
be along the track afterwards known as the Kentish Watling Street. For
here again the late British legends which tell us of councils of war
held in London against Caesar, and fatal resolutions adopted there,
with every detail of proposer and discussion, are probably founded,
with gross exaggeration, upon a real kernel of historic truth. It was
actually on London that the Britons retired, and from London that the
gathering of the clans broke up, each to its own.

SECTION G.

Passage of Thames--Submission of clans--Storm of Verulam--Last patriot
effort in Kent--Submission of Caswallon--Romans leave Britain--"Caesar
Divus."

G. 1.--Caswallon, however, and his immediate realm still remained to
be dealt with. His first act, on resolving upon continued resistance,
would of course be to make the passage of the London tide-way
impossible for the Roman army; and Caesar, like William the Conqueror
after him, had to search up-stream for a crossing-place. He did not,
however, like William, have to make his way so far as Wallingford
before finding one. Deserters told him of a ford, though a difficult
one, practicable for infantry, not many miles distant. The traditional
spot, near Walton-on-Thames, anciently called Coway Stakes, may
very probably be the real place. Both name and stakes, however, have
probably, in spite of the guesses of antiquaries, no connection with
Caesar and his passage, but more prosaically indicate that here was a
passage for cattle (Coway = Cow Way) mark