the tides the Mersey would be
a wretched dribble not much bigger than it is at Warrington. With them,
this splendid basin is kept open, and a channel is cut of such depth
that the _Great Eastern_ easily rode in it in all states of the water.

The basin is filled with water every twelve hours through its narrow
neck. The amount of water stored up in this basin at high tide I
estimate as 600 million tons. All this quantity flows through the neck
in six hours, and flows out again in the next six, scouring and
cleansing and carrying mud and sand far out to sea. Just at present the
currents set strongest on the Birkenhead side of the river, and
accordingly a "Pluckington bank" unfortunately grows under the Liverpool
stage. Should this tendency to silt up the gates of our docks increase,
land can be reclaimed on the other side of the river between Tranmere
and Rock Ferry, and an embankment made so as to deflect the water over
Liverpool way, and give us a fairer proportion of the current. After
passing New Brighton the water spreads out again to the left; its
velocity forward diminishes; and after a few miles it has no power to
cut away that sandbank known as the Bar. Should it be thought desirable
to make it accomplish this, and sweep the Bar further out to sea into
deeper water, it is probable that a rude training wall (say of old
hulks, or other removable partial obstruction) on the west of Queen's
Channel, arranged so as to check the spreading out over all this useless
area, may be quite sufficient to retain the needed extra impetus in the
water, perhaps even without choking up the useful old Rock Channel,
through which smaller ships still find convenient exit.

Now, although the horizontal rush of the tide is necessary to our
existence as a port, it does not follow that the accompanying rise and
fall of the water is an unmixed blessing. To it is due the need for all
the expensive arrangements of docks and gates wherewith to store up the
high-level water. Quebec and New York are cities on such magnificent
rivers that the current required to keep open channel is supplied
without any tidal action, although Quebec is nearly 1,000 miles from the
open ocean; and accordingly, Atlantic liners do not hover in mid-river
and discharge passengers by tender, but they proceed straight to the
side of the quays lining the river, or, as at New York, they dive into
one of the pockets belonging to the company running the ship, and there
di