NEW LOCK AT BREMERHAVEN.
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invert in the floor of the look has been dispensed with as unnecessary, since
no springs were likely to be fbund in the stiff clay on which the lock stands.
The walls, which contain the levelling culverts, are founded on inclined
piles, in rows, 4 feet apart. They are inclined alternately in opposite
directions, an arrangement which secures a favourable distribution of the
forces acting on the piles, and has the further advantage that the pile-heads
are not so near together, and the piles can consequently be driven deeper
into the solid ground. The inner end of the lock is closed by a sliding
caisson, the outer end by a pair of iron gates. The former was selected on
grounds of economy and utility as a movable bridge, the latter by reason of
their greater strength, for during spring tides a strong current flows through
the lock into the Kaiser Dock, which during southerly winds is considerably
increased by the heaping up of the tide on the Bremerhaven shore. This
current, aided by the force of the waves and the pressure of the wind,
exerts a force which, it was considered, could not be so well resisted by a
sliding caisson, supported at one end only, as by two strong gates.