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If the charges are all fired at high water, no fear need be entertained of any damage to adjacent property, as the head of water above the rock is amply sufficient to confine the explosive action.

ENTRANCE CHANNEL.

Beyond the removal of the Channel Rock, I am not prepared to recommend any attempt to improve the channel at the entrance.

Though the sharp turn in it calls for great watchfulness and skill on the part of pilots, experience proves that with good pilots, a channel of a kind are exceedingly rare; and the unchanging depth of water on the bar appears to indicate that the action of the various currents of ebb and flood in the Harbour and the Waimea Inlet has attained a permanent balance, which might not unlikely be disturbed by any change. A rubble causeway could certainly easily be constructed from the shore to the Arrow Rock, and the mere facility of access to the rock itself would often be in many respects a great convenience, while the causeway would confine the tidal currents and probably cause the inner end of Haul-ashore Island to be scoured away, to the improvement of the channel. As, however, the effect on the bar of any such change in the direction of the currents cannot be predicted with any certainty, and as no pressing need for such a causeway exists, it had better not be attempted, at least until it is more really necessary than at present.

WHARFAGE.

The simplest and most expeditious method of increasing the wharf accommodation of the Harbour, would certainly be to extend the present Government Wharf towards the entrance as shewn; and as sufficient depth of water for vessels of any size could be obtained alongside such a wharf without dredging, it would also be, at least in the first instance, the most economical.

The plan shows an extension of the outer T or head of the present wharf, of about 25 chains in length, with approaches every 7 chains apart, and a certain amount of reclamation (to low water mark) alongside the Haven Road; but any smaller lengths could of course be constructed. The spaces between the approaches could be leased for stores and goods sheds, on condition that all such works should be constructed on piles at not less than a stipulated minimum distance apart so as not to contract the water way unduly.

Another method of obtaining increased accommodation would be by works above the present wharf. The plan shews a shipping basin with 94 chains of wharf frontage and a water area of about 31 acres; the basin is proposed to be comparatively narrow at the entrance and at the upper end, but wide enough in the middle to allow of the longest vessel being "canted" without difficulty, even if two tiers of vessels were moored on each side. But for the necessity for dredging, this wharfage could be constructed considerably more cheaply than than that below the present jetty, and, even allowing for dredging, it should not be much more expensive yard for yard; while the more perfect shelter afforded to shipping, and the much greater susceptibility of expansion which any wharfage above Green Point must possess, are strong arguments in its favour. Moreover, as all warehouse sites would be on reclaimed land, thus admitting of the erection of more solid and permanent structures, they ought to fetch a correspondingly high price, if not placed in the market more rapidly than required. The shipping basin is designed to be dredged to a depth of 22 feet at low water alongside the wharves throughout, and to a depth of 22 feet at high water

over the wider space in the centre, as it is not necessary that it should be able to be canted at all times of tide. Further information as to the nature of the bottom and the depth which rock is met with would be necessary before any plan for such a shipping basin could be finally matured, and many other arrangements, perhaps equally good as that shown, might be proposed; but the general principles must be the same in all, and so long as the Maitai River is diverted and the basin laid out nearly in the proportion to the design on the plan will probably be found to be at least as convenient as any other which can be laid out.

All the wharfage, whether along Haven road or above Green Point, is proposed to be of squared timber, framed somewhat as shown on figs. 1 and 2, and of sufficiently massive construction to adapt it for berthing heavy vessels; the piles and other timber in water to be of West Australian mahogany, as that wood has the property of resisting the attacks of the marine worm more perfectly than any other known, and in some works is still sound after 35 years' exposure in seas in which other timbers have been rapidly destroyed.

RIVER DEFLECTION.

As an essential part of any scheme for constructing a deep still-water basin for shipping, it is proposed to exclude the Maitai River, so as to prevent any tendency to damage to shipping from the velocity of flood currents, and, which is of much greater importance, to free the basin from deposits of shingle which would otherwise of necessity take place. The line in which the river is proposed to be trained is a gentle curve from its present principal outlet, and it is laid out, so far as practicable, so as to take advantage of one of the existing channels, and reduce the amount of excavation required to a minimum.

RECLAMATION.

Between the proposed basin and the new course for the river, the whole area would be reclaimed as desired, and the land thus obtained ought to fetch a very high price for business purposes.

As a general principle, it is not advisable to reclaim any very considerable portion of the area of a Harbor and the land thus obtained to exclude tidal water, as it is established that the tidal flow is of vital importance in maintaining the depth on the Bar; and consequently the theoretically most correct method of proceeding is to reclaim only to half-tide level, and to excavate from thence at least to the level of low water, thus maintaining the tidal capacity of the Harbour unimpaired, though diminishing its superficial area; and it must be remembered that excavation below low water of spring tides has no more effect in admitting an increased amount of tidal water than any amount of filling above high water has in excluding it. There are, however, localities where a very large tidal basin has a contracted entrance, and in such a judicious reduction of the tidal area has had a beneficial effect; the reason being that under such circumstances, though the current is very rapid in the entrance, the basin has not time either to fill or empty completely during a tide, and thus, while the high water is lower, the low water level is higher, inside than outside. Reclamation up to a certain point in such a harbor will not at all diminish the amount of water passing in and out every day, but will only allow the tidal levels inside and out to assimilate; if carried beyond that point, reclamation will probably be injurious.