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Methods of Working. — From the winding levels drifts were driven due west and practically parallel with the Wellington main haulage roads. For a distance of 27 yards from each shaft these drifts are of shaft width, 15 feet in height and arched; they then taper down to 13 feet wide and 9 feet high, and are supported by brick side walls and girders. These drifts are being driven seaward in order to connect the Haig shafts with the workings in the Saltom area of the Wellington Pit The drift from No. 5 pit holed at a distance of 1,400 yards into a similar drift driven landward from Wellington Pit workings, on the 19th July, 1922. The drift from No. 4 pit is still under construction and has not yet holed through. On the Wellington side, winnings were driven both landward to hole into Haig Pit, and also seaward to win an area of the Main Band Seam; the total distance to the face after holing was 3,900 yards in a direct line from Haig Pit. As these winnings advance, it is intended to make connections to the more remote districts of the Wellington Pit. In driving landward in the Main Band Seam, a series of faults was passed through and eventually the Six Quarters Seam was cut.

In crossing the measures with the drifts from the Haig Pits the Six Quarters Seam was cut in December, 1921, at a distance of 830 yards from the shafts, and on the south side of a large fault running on the north side of the drifts and almost parallel with them. The drifts were continued in the Six Quarters Seam for a further 570 yards, when they holed into the drift driven from the Wellington workings.

A small area to the south in the Six Quarters Seam, known as the South-West District, was opened out from the main drifts and was being worked at the time of the explosion.

At a distance of 350 yards from the Haig Pits a pair of drifts were driven northward through the fault previously mentioned, and the Six Quarters Seam was cut in December, 1919, and was subsequently opened out. This was the only area affected by the explosion.

At a further distance of 180 yards a pair of similar drifts were driven, and the Little Main Seam, lying 12 fathoms above the Six Quarters, was cut in April, 1920. This seam is 2 feet 3 inches thick, and a small longwall area was worked by compressed-air coal-cutting machines, but was suspended on the 11th March, 1922, on account of shortage of men.

The section of the Six Quarters Seam in the inbye area is :—

Roof	Black Shale.
	Upper Coal	1 ft.	4 ins.	to	1 ft.	10 ins.
	Black Shale	2 ft.	0 in.
Portion	Coal	3 ft.	5ins.	to	3 ft	7 ins.
worked	Band		¾ in.	to		10 ins.
	Coal	2ft.	0ins.	to	2ft	4 ins.

In the outbye area of the district, which is to the rise, the band was so thick that only the upper section of the seam was extracted by the longwall method. The gateways were 13 yards apart and height for the tub roads was made in the roof. Where the band was thinner, as in the inbye area, the whole of the seam was extracted by the bord and pillar method. The workings were 4 yards wide and the pillars were 40 to 50 yards square.

The seam has a general dip to the north-west of 1 in 9, but owing to local variations roadways which had been set away level course were dipping near the face.

A certain amount of water was made in the district and three small compressed-air pumps. were installed to deal with it, one being placed at C, one at D, and the other at E on Plan No. 3. The management also stated that the workmen at the face were encouraged to fill the water into the tubs with the coal.

The floor of the haulage plane was more or less wet from below the No. 1 air crossing (see Plan No. 3) to the face of the dip, pools forming in some places. The floor of No. 1 level was also wet and water stood for several yards at various points. It is also possible that leakage of the water filled into the tubs with the coal tended to some extent to keep the floor of the roadways damp, if not wet, except in some of the roads to the rise in the longwall area.

No coal-cutting machines were in use, the coal being undercut by hand to a depth of 2 feet to 2 feet 6 inches, but it is clear that the holing was not always made to this depth. The undercutting was done in the shale band where it was of sufficient thickness, but in one or two places in the bord and pillar and the longwall face the holing was done in the upper section of the seam. The coal was then got down by blasting, usually three shots being fired in the upper section and three in the lower section. The dirt from the holing in the band was thrown back to the sides of the workings, the tub road being in the centre.

The roof of the seam is a very friable black shale intersected by a large number of slippery partings, necessitating the use of props and bars. The following timbering distances were fixed by the manager in accordance with Section 50 (4) of the Coal Mines Act, 1911 :—

(a) Between each row of props, 4 feet.

(b) Between adjacent props in the same row, 5 feet.

(c) Between the front row of props and the face, 4½ feet.

(d) Between the holing props or sprags, 6 feet.

The timber at the face was set by the hewers, while the backbye timber was set by shifters.

The engine plane has brick side walls carrying steel girders for a distance of 230 yards, and for the remainder of the distance steel girders and wooden bars supported by props. The plane averaged 11 feet wide by 6 feet 6 inches high.

Two men worked together in each working place and got, filled and trailed, or hauled, their own tubs to the haulage plane. There were no putters' flats or sidings in the district. No horses are employed at any of the Whitehaven pits; this necessitates in dip places the use of jack rolls and small compressed-air haulers (windy putters). In the rise places self-acting inclines or dillies were used. The main haulage plane was worked by endless rope which extended to the bottom level, the return wheel being situated just below the level and placed horizontally on the floor. Two sets of rails are laid nearly to the bottom of the dip, but the empty road was being extended to form a double track the entire distance.

Ventilation. — Before the holing to the Wellington Pit was effected in July last, the total quantity of air passing down the Downcast shaft was 40,800 cubic feet per minute. Of this quantity 16,800 cubic feet passed into the North District of the Six Quarters Seam, the measurement within 100 yards of the first working place being 6,000 cubic feet; while 9,250 cubic feet went into the Little Main Seam, and 13,600 cubic feet into the Drift District. After the holing, the total quantity of air passing through the Downcast shaft was 76,635 cubic feet per minute, and this was distributed as follows: 20,240 cubic feet passed into the North District of the Six Quarters Seam, the measurement within 100 yards of the first working place then being 7,300 cubic feet; 5,000 cubic feet went into the Little Main Seam, 9,120 cubic feet in the South-West District of the Six Quarters Seam, and the remainder travelled through to Wellington Pit.

Up to July, 1922, the North District of the Six Quarters Seam was ventilated by one continuous split of 16,800 cubic feet per minute passing down the main engine plane, round the workings and over the No. 1 air crossing shown on Plan No. 3. After the holing, it was found that the pull exerted by the Wellington fan to some extent interfered with the ventilation of the Six Quarters Seam in the Haig Pit; a second overcast was therefore constructed at the point shown on Plan No. 3. The air was then taken down the main engine plane and after passing round the lower workings (bord and pillar) 10,395 cubic feet per minute were allowed to pass over the No. 2 air crossing; the remainder passed into the longwall workings joined by the leakage along No. 1 level, and after coursing round the longwall workings passed over the overcast "A" into the return. 12,925 cubic feet per minute passed through this overcast. In addition, a canvas regulator was placed in the drift leading to Wellington Pit, and the quantity of air passing after these alterations showed an increase of 3,080 cubic feet per minute passing into the North District, making a total quantity of 23,320, according to notes made by the Manager at the time of the alterations.

The barometer and the hygrometer were read and recorded in the prescribed book as required by General Regulations 104 and 105.

Plan No. 2 shows the method of ventilating the North District prior to the explosion, and also the position of the doors and stoppings and the probable position of the brattice to convey the air to the face of each working.

Plan No. 6 shows details of the construction of the air crossings. Brickwork 14 inches thick was used for the side walls of the overcasts and also for the three necessary permanent stoppings.