CO129-350 - Public Offices - 1908 — Page 207

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"A", shows by red colour the position and extent of the

works proposed. The average depth on the line of the

Breakwater, above the surface of the mud, may be taken at

18'0" at low water. Along this line it is proposed to

dredge a trench to receive the base of a rubble mound,

and to form a structure thereon largely consisting of

"pierre perdue" brought up to within 7'0" of low water

level on the sea side, and there faced with concrete in

bags.

The slope on the Harbour side would also be of

rubble, up to ordnance datum, and there capped with a

single layer of concrete in bags. The superstructure

above low water would consist of hand packed etone,

faced with granite pitching laid on cement concrate, on

the sea slope, and on the harbour side by pitching laid

dry, the latter mode of construction being adopted with a

view to obviate the formation of compressed air within

the work.

18.

Trial holes have been made at intervals along the

line of the structure by means of a grab dredger, from

which it appears that the mud is very soft on the surface

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