the adjacent faces of each sloping section,
extending from top to bottom of the sections. These, when settlement
on the mound had ceased, were filled with concrete in bags which not
only connected the tiers of blocks in each section together, but also
joined the several sections to one another, and effectually closed
the transverse joints between the successive sections, which were
further connected together by a continuous capping of concrete-in-mass
along the whole length of the breakwater.

These sloping blocks are laid by powerful overhanging, block-setting
cranes, called Titans (see CRANES), which travel along the completed
portion of the breakwater, and lay the blocks in advance on the mound
levelled by divers, as shown in fig. 10. The earlier Titans, employed
for the sloping-block superstructures at Karachi and Madras, were
constructed to travel only backwards and forwards on the completed
work, with sufficient sideways movement of the little trolley
travelling along the overhanging arm, from which the block is
suspended at the proper angle, to lay the blocks for each side of the
superstructure. In later forms, however, such for instance as the
Titan laying the 14-ton blocks at Peterhead breakwater in horizontal
courses, the overhanging arm is supported centrally on a ring of
rollers, placed on the top of the truck on which the Titan travels, so
that it can revolve and deposit blocks at the side of the
superstructure for protecting the mound, as well as in advance of the
finished work. These Titans possess the important advantage over the
timber staging formerly employed for such breakwaters, that, in
exposed situations, they can be moved back into shelter on the
approach of a storm, or for the winter or stormy months, instead of,
as in the case of staging, remaining out exposed to the danger of
being carried away during stormy weather, or necessitating loss of
time in erection at the beginning of the working season.

[Illustration: FIG. 11.--Marmagao Breakwater.]

Though composite breakwaters are still occasionally constructed with a
superstructure founded on a rubble mound at, or above, low-water
level, these breakwaters are now almost always constructed with the
superstructure founded at some depth below low water, even at harbours
on the continent of Europe, where formerly broad quays founded at
sea-level, protected by a parapet wall a