259

GENERAL ESTIMATE—Continued.

BRIDGES—

Wairaki Stream .......................... £50 0 0
Waimatua ............................... 250 0 0
Mokotua ................................. 250 0 0
Mokomoko .............................. 300 0 0
————————
850 0 0

CULVERTS AND OUTFALL DRAINS—

54 Culverts, at £30, and sundry Open Drains ............... 2000 0 0

STONE PITCHING AT FOOT OF EMBANKMENT—

2800 square yards, at 15s ................................. 2100 0 0
Stations, as per estimate .................................. 8300 0 0
Rolling Stock, as per estimate ........................... 12300 0 0
Engineering, 2½ per cent .................................. 2500 0 0
————————
£109,967 0 0
Deduct Earthworks, &c., for Highway, say .................. 5000 0 0
————————
£104,967 0 0

REPORT OF J. F. DUNDAS ESQ., C.E. ON THE INVERCARGILL AND CAMPBELLTOWN RAILWAY.

Invercargill, 23rd February, 1863.

SIR,

IN compliance with your desire, I have now the honour to report that along with Mr. Heale, the Provincial Surveyor, I examined on 26th and 27th ult., the course of the proposed Invercargill and Campbelltown Railway.

Since then I have had repeated interviews with him, and have, along with him, gone over the plans, sections, and estimates.

It will be quite unnecessary for me to enter upon any minute description of the course of the line or proposed works, as these will no doubt, be described in detail by Mr. Heale.

The country, as is very apparent, affords unusual facilities for the construction of a railway of superior curves and gradients at a moderate cost.

Considerable care and judgment have been necessary in the selection of the ground; not only to the northward of the Mokomoko Range, but also in the portion along the margin of the Bluff Harbour. All of this has been done with great judgment by Mr Heale, and I am quite satisfied that the best ground has been chosen.

The works are of an unusually light character, and there is an almost entire exemption from that formidable source of expenditure to railway companies—the necessity for frequent crossings by means of bridges over or under the railway; in the present case there being only necessary, on account of either public or private interests, a single crossing in the whole length of the line.

Material for ballast, and timber for sleepers, are in abundance on the ground; and, altogether, it has not hitherto fallen to my experience to see a line of the same length which could be constructed under such favourable circumstances.

The only points in connection with the works appearing to require special mention are—the crossing of the peat lands to the northward of the Mokomoko Range; the rock cuttings and steep gradients at that point; and the embankments at the margins of the small bays in the Bluff Harbour.

With regard to the first of these no difficulty need be apprehended; the main precautions will be—after proceeding, as proposed by Mr. Heale, to dig the ground and lay fascines—to avoid, wherever practicable, breaking the surface, and keep the embankments sufficiently high to provide for shrinkage.

It is proposed temporarily, at the outset, to cross the Mokomoko range by means of ascending and descending gradients of 1 in 58. This course may perhaps be financially expedient, but the traffic will for the time be materially inconvenienced, and I think should the Provincial Government feel in a position to cope with it at once, the advantage of materially reducing these gradients is very obvious.

Practically, unless sidings are put in on both sides of the summit, the effect will be to limit an engine train to about one-fifth part of the load it could take along the rest of the line. Were the probable traffic steady and moderate in amount, this would be less objectionable, but, as in the case of a ship discharging or taking in cargo, when the occasional conveyance of considerable quantities in a limited time is necessary, the inconvenience and expense of working would materially tell.

No doubt, by putting in sidings and dividing the trains, the evil may be somewhat diminished, but still the inconvenience of stopping the way, and the delay and expense of shifting about the waggons between two points a considerable distance apart would be considerable.

Nor need, in my opinion, the lowering of these gradients necessarily cause delay in the completion of the line for traffic,—the material as excavated may be stacked by the