E.— 2

5

beach, at a cost of about £900. The work is now complete so far as the reparation of immediate damage goes. The clay bluff immediately to the northward of our work at Whale's Creek, between it and the next viaduct, is being steadily undermined. It is sufficiently far off not to hurt at present ; but if the process continues more rock will have to be put down, extending northward. With regard to the travel of the shingle, and the observation you made that there was encroachment by the sea southward of the breakwater, I have noticed that this is clearly the case, but feel satisfied by frequent observation that it is accounted for thus : The sea is continually surging the shingle northward. It is interrupted in its progress at the breakwater and accumulates there. The deposit of shingle does not take place to any great distance back —in fact, very little additional beach is made further south than the point immediately south of the southern boat-landing stages. The action of the sea in sweeping the shingle northward is comparatively regular in calm weather, and the beach presents an even and regular appearance; but in heavy gales the action is violent and irregular, and, while the general tendency of the shingle is northward, in doing the work the sea scoops the shingle out in some places and piles it up in others. This leaves the beach irregular after gales, and there is the appearance of encroachment in the places where the shingle happened to be rushed out at a more than ordinary rate. This irregularity is by slow degrees toned clown afterwards until another gale makes more encroachment. The second series of encroachments are, however, not likely to be in continuation of the last, but more power will be bestowed on the lumps. There is, however, no great nicety observed by the sea; and, considering the force it can exert, and the lively nature of the shingle, it seems remarkable that the alterations or temporary encroachments made along the beach are not more extensive. The main fact remains as clear as ever that the breakwater intercepts the general progress of the shingle, and the beach to the northward remains denuded. A small quantity of the shingle occasionally gathers along the shore from the Government Landing Service to Whale's Creek, but it as often disappears again. After you were at Timaru, and a recommencement was made at the breakwater, great difficulty was experienced from the quantity of shingle that was found at the end. The shingle had filled up the bight caused by the mole, and was forming a beach round the end, and no doubt before long there would have been a fine beach beyond the mole, the end of which would have been buried in the debris at high-water mark. The blocks consequently did not find a bottom, and the delays entailed made it apparent that the shingle could pile up as fast as the breakwater could be built. They then tumbled blocks in roughly, and so got to the end of the shingle, and from that point began again the permanent structure with the foundation blocks on the bottom. It is therefore evident that any delay of four or five weeks will be sufficient to allow the shingle to overtake the work again. The idea of the Harbour Board was that the shingle would be deposited in layers somewhat parallel with the beach, as in sketch A,* so that the quantity stopped by equal lengths added to the mole would increase in a great ratio. This does not appear to be realized, but, on the contrary, the accumulation seems to be forming as in sketch B.f In this event the chance of ever keeping permanently ahead of the shingle seems greatly reduced. The Engineer to the Harbour Board, in a recently-published report, states that he has computed that the accumulation of shingle on the south side of the breakwater for twelve months could be carted across to the north side for£l,ooo. A question arises whether this (if continued where the breakwater has been extended sufficiently to give still water on the north side) would not block up the harbour. J. Henry Lowe, The Colonial Marine Engineer. Resident Engineer.

No. 5. The Commissioner of Railways, Middle Island, to the Colonial Marine Engineer, Wellington. Sir,— Christchurch, Bth January, 1880. The Resident Engineer has handed me the enclosed report (No. 2) upon the encroachments at Whale's Creek, Timaru. I can fully indorse the statements of the Resident Engineer, and need hardly point out to you the serious urgency of the case, so far as the safety of the railway is concerned. I beg you will do me the favour to submit the report at your very early convenience to the Hon. the Minister for Public Works. I have, Sec, Wm. Conyers, The Colonial Marine Engineer, Commissioner of Railways, Middle Island. Wellington.

Enclosure in No. 5. Memorandum for the Commissioner of Railways, Middle Island, Christchurch, re Encroachment at Whale's Creek, Sec, Timaru. Resident Engineer's Office, Christchurch, 6th January, 1880. In accordance with your instructions of the 15th ultimo, on your M. 79-388, I forward attached hereto my report (No. 2) on Whale's Creek encroachments for the Colonial Marine Engineer. J. Henry Lowe, The Commissioner of Railways, Middle Island. Resident Engineer.

* See plan attached, No, 8. t See plan attached, No. 9,