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To effect the above it is recommended that channel No. 3 be first closed—which will not only prevent any further deposit on the mud bank in front of it, and which is the most prejudicial in the Harbour, but as the water so shut off must augment the volume passing through channel No. 2, it must necessarily increase the scour and deepen its bed, and at the same time aid in removing the bank which it has itself formed. The cost of closing this channel would not exceed £100, as the work required would be of the most temporary nature, to serve only until the execution of the 3rd and 4th Sections of the work.

The 2nd Section to be carried out, should be that marked by two strong red lines and numbered 2 on plan, the length being about 600 feet and estimated to cost £2,200. This would form a portion of the permanent work, and the line of Piles would be driven in an average depth of 5 feet at low water. They must be driven deep to obviate the risk of scouring the foundations, hence, comparatively, the greater cost of this portion of the work.

The third Section would be that immediately opposite the latter, marked by a single red line and numbered 3 on plan, extending about 1000 feet, the greater part of the site being dry at low water, with an inconsiderable portion at the western end running into a depth of 8 feet at low water; but as the ebb tide would have no tendency to scour the foundations, it would be of less costly construction than the last Section; although, forming part of the permanent work and being adjacent to that part of the canal which would be first dredged out, it would be more costly than the bulk of the work, which is indicated by a single blue line. The estimated cost is £1800.

On the completion of this Section a Dredging Machine would be required, to remove the mud bank opposite the Iron Pot, and to dredge the canal to a depth of 15 feet at low water, to within 20 feet of either side. This Dredge need not be a very powerful one, and owing to the small rise of the tide must be of very light draught, or it could not be placed on the banks it would be required to remove. The Engine and Apparatus should be procured either from Sydney or England, and the Hull built on the spot. The probable cost will be £2000—or, if to avoid delay the Apparatus is procured from Sydney, it may cost £500 extra.

The 4th line of Piling to be carried out, should be that marked by a double red line and numbered 4. This Section would be exposed to a severe scouring action on account of the ebb tide setting towards it across the main channel. The length will be about 800 feet, and the cost £3000,—the construction being similar to that for Section No. 2 but the Piles must be driven deeper.

The 5th Section would be that running South from the Meanee Spit, a distance of 2,500 feet, which would divert the Tidal Stream from the shore of the Spit, and as the whole ebb and flow of the tide must then pass between the extremity of this line of work and Battery Point, it would give the current a direct course out of the Harbour and over the Bar. The tide would no longer be obstructed and diverted at the outlet and the depth on the Bar would be increased. The average depth on this line would not exceed 3 feet, although a portion of it would be executed in 9 or 10 feet at low water. The cost is estimated at £6,500.

As this line of work would concentrate the whole flow of water for about half a mile inside the Harbour to a comparatively narrow and well defined channel, there would be sufficient scour over that area to deepen it to 15 or 16 feet, with very little assistance from the Dredging Machine, and this extended area of deep water would greatly facilitate the movements of vessels either on entering or leaving the Port.

The 6th and last Section would comprise the whole of the temporary works before alluded to and shown on plan by a single blue line, presenting a total length of 12,700 feet at an estimated cost of £10,400. This work would consist of Piles driven about 5 feet apart, and covered with horizontal planking, but instead of at once carrying the planking above high water mark to the datum line, the planking should first be carried all round to the height of 9 inches or 1 foot above low water, and so left for a period, thus allowing the alluvions brought down by the floods to be spread over and deposited on the surface to be reclaimed; and as soon as it had silted up to the level of the planking, another plank should be carried all round, and so on till within a few inches of high water mark, when the planking