Page:Our New Zealand Cousins.djvu/175

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Our New Zealand Cousins.
159

a solid breakwater of concrete blocks thirty-six feet wide, reaching to half-tide in height; then capped with a monolithic concrete block of about five hundred tons in weight. This wall was to extend to about 1000 feet from low watermark in a north-east direction, and then turn in a northerly direction 700 feet or 800 feet; it was to be six feet above high water spring tides, and would have twenty feet of water at spring low tides at the extremity. The work was started and succeeded, withstood the force of the waves, and was not swallowed up by the travelling shingle, which was swept back by the backwash of the waves. This backwash is caused by the reflection of the waves from the face of the mole; it sweeps back the approaching shingle, or retards its advance, and by its action the shingle line adjacent to the breakwater has been stationary for the last four years. When the works were carried out 1000 feet, its success was so self-evident that the Harbour Board determined to extend the mole another 400 feet, and the cant to the north to 200 feet, and also to strengthen the section. It is also proposed to build a mole from the shore on the north towards the extremity of the cant, and so produce a nearly enclosed harbour. The area of this harbour will be 180 acres, and when completed, will be perfect and commodious. Now, although only a small portion of the cant has been built, along with the straight mole from the shore, accommodation gained is already invaluable. Vessels of 1000 tons can anchor to the lee of the break-