CO129-350 - Public Offices - 1908 — Page 208

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but gradually increases in stiffness towards the hard

bottom, which generally consists of yellow earth, sand or decomposed granite, lying at a depth of from 30 feat to 50 feet below low water, and from 5 feet to 32 feet below

the surface of the mud. It was with a view to reduce the

lateral spreading or lifting of this mid, as the rubble is

tipped, that the dredging was recommended, and in the ne

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cessity for this procedure we entirely concur. It is im...

portant, however, that the deposit of the rubble to form

the base of the Breakwater, should be made from time to

time, as the dredging, required in connection with the formation of the trench, has been completed over a given

length, and prior to mud deposits having occurred therein.

19.

It is proposed to obtain the rubble of all sizes

for the work, from the boulders and stones lying on the

ahores in various localities.

The general distribution

of the relative sizes required to form the mound,

has been described to us by Mr. Boulton, and appears to

be well conceived and adapted to form a structure of the

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