Dr. Hector to the Hon. The Colonia Secretary.

I have the honour to report that, in accordance with your instructions, I have surveyed the Collingwood Coal Mine, and made an estimate of the probable length of the tunnel recommended in a former report, with the view of ascertaining if the grant of £500 made by Government will be sufficient to enable the Company to carry out the work.

The Company, anticipating that they would receive assistance from Government, had the tunnel commenced in September last, under the enclosed contract, at the rate of 30s. per foot.

The tunnel, on the 25th ultimo, had been carried forward 102 feet, at an average rate of progress of 10 feet per week. The contract provides that only 75 per cent, of the amount done from time to time is to be paid to the contractors; but the Manager having, at their pressing solicitation, advanced the full amount, the contractors have taken advantage of this and abandoned the contract. This will cause some delay while fresh tenders are being called for; and I also doubt if a new contract will be obtained at the same rate as the first (which is very much below my previous estimate of 50s. per foot) notwithstanding that the hardest part of the rock has now been cut through.

A plan and section of the mine is being prepared from my survey, and will show the nature of the rock and the extent of the field that will be opened up by it.

The height of the workings above the drive I determined with a pocket level, and the remainder of the altitude by the aneroid barometer.

The direction of the drive was checked, and found to be within 1 degree of a line at right angles to the longest level course in the old workings.

The dip of the strata was determined at several points, and an average of 1 in 3 taken as the most reliable for the beds through which the tunnel will pass, although subject to variation in other localities in the immediate vicinity.

From these data the lowest known seam of coal, 1 foot thick (No. 6 of former report), should be cut at 140 feet in the drive, or about 40 feet further than its present extent; the lowest seam that has been worked (No. 4), at 330 feet; the middle seam (No. 3), at 540 feet; and the upper or main seam, that has been worked, at about 600 feet.

The following is an approximate estimate of the character of the rock that will be passed through:—

A beady Driven.

	Feet.
Gray sandstone, with coaly layers in thick beds, with intervening bands of very tough breccia	102
Gray sandstone, with bands of breccia from 1 to 3 ft. thick; shale partings at 3 to 8 ft.	40
Coal	3
Gray sandstone and ironstone shales, with thin layers of breccia; frequent clay partings	240
Coal	3
Gray sandstone and black shale	48
Fine-grained breccia	24
Gray ironstone	9
Carried forward	469page 28
Brought forward	469
Coal	2.5
Gray sandstone	36
Coal and shale	3
Gray sandstone	6
Ironstone shale	3
Gray sandstone	12
Coal	4
Ironstone shale	12
Clay band	12
Coal	4
Ironstone shale	7.5
Gray ironstone	4.5
Coal and shale	9
Coal	3.5
Shale	3
Clay iron band	1.5
Coal	2
Clay iron band	1.5
Coal	5
Coal and ironstone band	12
Total	613

This does not differ materially from my former estimate, £1,125; and until the work has made further progress, I do not recommend that the application for increased assistance beyond the £500 already granted should be considered.

With regard to the manner in which the Government grant will be paid, I have arranged with the Manager of the Company, in accordance with your authority conveyed by telegram, that 75 per cent, of the amount due under contract for driving the tunnel will be paid from time to time on the certificate of His Honour the Superintendent. A first payment has been made under this arrangement, page 29 being the proportion due on the 102 feet excavated by the late contractors.