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The System of Ventilation. — At the time of the explosion the ventilation was produced by a fan, of the Walker indestructible type, placed on the surface and driven by a compound engine in good condition. The fan which is 24 feet in diameter and 8 feet wide at the vanes, exhausts from the upcast shaft being driven at a speed of 34 revolutions a minute, and inducing a current of 50,000 to 55,000 cubic feet at the bottom of the downcast shaft, but the total quantity of air exhausted by the fan is between 78,000 and 85,000 cubic feet made up of the Wellington Pit air, part of the air from the William Pit, and surface leakage. The fan was working at 6.7 inches of water gauge, and was capable of producing 150,000 to 200,000 cubic feet of air per minute. The high water gauge was attributed to the heavy frictional resistance due to the great length of airway and the leakage underground. The current from 50,000 to 55,000 cubic feet of intake air was disposed of as follows :—

The current continued along the main intake without a "split" being taken off it, until the Saltom district was reached where a "split" was taken off to ventilate the workings there. Another was taken off at the 3rd North way-end to ventilate that district, and the remainder of the air passed inbye to the 6th North. The course of the current being indicated on Plan II., from which it will be seen that the 5th North was ventilated with the return air from the 6th North, with such additional air as scaled through the separation doors DD placed on the mechanical haulage road of the 5th North. The current from the 5th North, having ventilated the workings by the route indicated in the plan, passed into the main return airway, and being carried over the two air-crossings at the outbye end of the 3rd North intake joined by the return air from the 3rd North and proceeded to the upcast shaft by the somewhat tortuous route shown on the plan

The volume of air in the various currents was as follows :—

c. ft. per minute
As measured	at the bottom of the shaft	50,000
"	in the "Infidel" drift	39,000
"	at Benks' turn	29,000
"	at the 3rd North district crossing	13,000
"	at the inbye side of 3rd North way-end	15,000

The air can be accounted for, therefore, as follows :—

Leakage as between bottom of the downcast shaft and the "Infidel"	11,000
Used to ventilate the Saltom district	1,800
Leakage as between the Infidel drift and Benks' turn	8,200
Used to ventilate the 3rd North district	13,000
Used to ventilate the 5th and 6th North districts, and not allowing for leakage as between the point of measurement and the 6th North way end	15,000
	49,000
Loss by leakage, probably between Benks' and the 3rd North way-end	1,000
	50,000

That is to say, between the shaft and the 3rd North way end there was a leakage of over 41 per cent, and when the great distance which the air current has to travel from the points of measurement made in respect of the 3rd and 6th North splits is considered, it will be realized that a very considerable further leakage must have taken place, and that only a very small quantity of the total volume of air reached the face of the workings, i.e. the part of the mine where the firedamp is chiefly generated and the workmen are mostly engaged. There is in all coal mines a considerable amount of leakage of from the intake through separation doors, stoppings, and air crossings in the passage of the air current from the shaft to the various district splits, but the leakage in this case was excessive.

Taking into consideration the gassy character of the mine, I am of the opinion that the scheme of ventilation adopted by the management was not well chosen. Thus the ventilation in the 5th North district with the return air from the 6th North was bad mining practice, for, as might be expected, it often contained gas. Thomas Graham, the overman of the second shift, found a ½-inch cap in the 5th North intake air in February, 1909, but since then had not detected the presence of gas at this spot — not since the 6th North restarted work (the 6th North was stopped on February 13th, and restarted on June 9th, 1909). He never reported finding the gas. Swinburne, who had 41 years' experience at Whitehaven Colliery, and who was a deputy in the 5th North district, had frequently found and indication of gas in the air entering the 5th North from the 6th North ; he last saw this indication as a ¼-inch cap of gas two or three days before the explosion. He never reported this however, not thinking it of any consequence. Mr. Steele, the manager, has found ?-inch cap in the last working place of the 6th North. Mr. W. C. Blackett, who, together with Mr. J. H. Merivale, was acting as technical advisor to the Colliery Company during the Inquiry, when asked what he would have done had he found a ½-inch cap showing at the end of the return from the 6th North district and before it entered into the 5th North district, candidly stated that he would have withdrawn the men from the 5th North — that is, had it been his own case.

The stoppings between the main intake and the return were built of brick and lime, and there were also 11 locked wooden separation doors in communications between the main intake and main return. The width between these roads (intake and return) varied from a minimum of 30 to a maximum of perhaps 200 yards. The management appeared to attribute the loss of air current to the difficulty of isolating the intake, to the extreme length of the road that it had to traverse, and the number of old workings that the main intake passed through. The stoppings separating the intake from the return air current in the districts were also substantially constructed of brick and lime. The air-crossings were built with a wooden top.

In the 3rd North there was a supply taken off the air current to ventilate the Stone-drift, see Plan II., this split being regulated with ordinary canvas doors down the drift ; after it had ventilated the drift the current passed along the old 4th North.

The current which ventilated the 3rd North "robbery" workings was carried up to the face by means of brick and canvas stoppings in the in-bye brake. It would have been better if the stoppings had been all of brick. The air for the whole of the return was regulated by a primitive sort of regulator, namely a canvas flap in the return airway — a sheet of canvas hanging down from a door frame. A regulator of this sort could be easily deranged or damaged. There should have been a proper regulator for so large a district similar in construction to that in the Saltom district, where a wooden sliding door was used which could be kept locked at the desired width of opening necessary for the proper regulation of the air. As a matter of fact, however, the "make-shift" regulator in the 3rd North return had not been tampered with. I merely mention its existence as pointing to a want of appreciation on the part of the management of what constitutes a proper ventilation arrangement. The air in the working places in the 6th North was conducted up to the face by means of canvas bratticing. Near the face in all the districts the stoppings were of canvas. It is the usual practice to make these temporary stoppings of canvas or wood.

The wooden separation doors on the haulage road of the 5th North were self-acting ; that is to say, the sets of tubs passing in and out opened them automatically. The first doors opened in the direction of the air current, and were closed again by balance weights. The in-bye doors opened in a reverse direction and did not require weights to close them. There was a considerable scale of fresh air on these doors. The assistant manager stated that they experienced most difficulty in the ventilation in the 6th North district, as on would imagine, seeing that it was the furthest in-bye and was entirely "in the whole" yet it was the air from this district which was used to ventilate the 5th North. In fact they considered the ventilation of the 6th North district so unsatisfactory that on February 13th, 1909, they laid part of it idle, and did not restart it until they had improved the ventilation.

That the management were evidently aware that the ventilation of the mine was unsatisfactory is evidenced by the fact that they had of late years been engaged in making the main road more air-tight by building side walls for some distance on each side of it, but further in-bye on the side next the return only. They had completed this work with the exception of about 200 yards and had just commenced on a large scheme of reorganisation of the ventilation which would have been completed within a month of the time of the accident.*

I asked the assistant general-manager whether under the circumstances — the great length of air roads passing through old workings — it would not be advisable to make the air return by a road driven in another seam, so as to avoid leakage, and he answered that they had already had such and idea under favourable consideration.

The reorganisation scheme consisted of erecting a Sirocco fan in the return at the point named the "fan-site" and driving the same by means of a steel wire rope carried from a point where the electrical driving plant was stationed. The effect of this fan would have been very greatly to augment the ventilation and in its introduction the management, were in my opinion well advised.

Now it will be observed that stoppings are shown in two roads leading from the ?? areas of goaf respectively in the 3rd North ; these roads constituted connections between the 3rd North and the old workings to the rise, and it was considered that unless these were stopped off the ventilation of the mine would be adversely affected by the suck on the old workings ; and I quite agree that that would be so, but I think a mistake was committed in erecting these stoppings before the scheme of auxiliary ventilation was complete and the underground fan ready to start, for these roads acted as the means of carrying out what is known as "ascencional ventilation" ; that is to say they acted as "gas taps" to the goaves, the current passing through them, small though it undoubtedly was, carrying away the firedamp collecting in the goaves. These stoppings were erected at the points A and B (see Plan II.): that at B in March 1910. That the roads in which they were erected did have a useful effect was evidenced at the time exploration work was being carried out when the mine was entered in the month of October ; for at one stage it was found impossible to further improve the ventilation in Nos. 1 and 2 Brakes until the stoppings at B (Plan II.) was broken down when a current of 680 cubic feet of air per minute passed up the top narrow road.

The mine would come under the designation "fiery." The Assistant General-Manager described the coal as "giving off gas freely," and seven or eight years ago they had had a considerable quantity of gas in 5 and 6 North districts when they were being opened out beyond some faults. He also stated, in examination by myself, that in the return airway at the "fan-site" the firedamp "cap" varied between one-sixteenth and one-eight of an inch. It may be taken, therefore, that under normal conditions at the mine the air current in the main return contained about 2 per cent. of firedamp.

The fact that there was 2 per cent. Of gas in the air of the main return might point to either "fiery" (gassy) colliery, or of an insufficiency of ventilation and I am of the opinion that it was indicative of both. Blowers of gas, though they had taken place from time to time, were not of common occurrence. It might be gathered from an inspection of the deputies reports that "gas" was seldom found in dangerous quantities in the mine, but this absence of report is not to be relied upon, as I shall presently show.

The ventilation was not, in my opinion, adequate within the terms of General Rule 1 of the Coal Mines Regulation Act.

Management. Inspection under General Rule 4. — The officials of the mine consists of the assistant general-manager, Mr. Blair, who has control under the agent Mr. James of all the mines ; under Mr. Blair was Mr. Robert Steele, who is the certificated manager for the Ladysmith and Wellington pits ; Mr. James Henry is the under-manager of the Wellington pit, and under him were three overmen, a master wasteman, a master shifter, and nine deputies.

The assistant general-manager, who had been connected with the colliery for eleven years, went down the pits frequently but not on every day. The manager who had that position for three years, went down practically every day, and Mr. Henry, who had been under-manager for about 20 years, every day.

The total number of persons employed underground at the Wellington pit was 723. The mine was worked by three coal-getting shifts and one repairing shift. On an average the coal hewers worked five hours at the face, the remainder of the shift being taken up in travelling to and from their work.

The time of descent of the shifts and the names of the overmen in charge are given below :—

			The overman in
			charge being
Morning shift	descended at	5.30 a.m.	J. Graham
Afternoon shift	"	11.30 a.m.	T. Graham
Night shift	"	5.30 p.m.	R. Cowie
Shifters	"	11.00 p.m.	The Master Shifter

Therefore at one period of the twenty-four hours two shifts of men were in the pit at the same time, the one going to work and the other preparing to leave work, but there was not continuous occupation of the working places within the meaning of General Rule 4 of the Coal Mines Regulation Act, 1887, so the working places were examined by the overmen and deputies before each shift and the reports recorded. Between the outgoing night shift and the incoming morning shift there was an interval, during part of which the night shift deputies carried out the statutory inspection of the working places. This inspection was made by one overman and three night shift deputies two hours before the morning shift came in. The deputies in charge of the incoming shift came down with that shift, but proceeded inbye in advance of the men in order to examine their lamps at the meeting station.

As the report book in which the statutory examinations are entered was kept in the office at the surface, a considerable time elapsed between the time of making the inspection and the entering of the report. This may perhaps be in legal compliance with the Rule which states that the report "shall be recorded without delay in a book to be kept at the mine for the purpose and accessible to the workmen," but cannot be regarded as fulfilling the spirit of that rule. It seems to me, also, a doubtful policy to have one, and that the most important, of the statutory reports made by deputies towards the close of their shift instead of by morning shift deputies on their first coming in when they would be much fresher for the work of travelling the face and their powers of observation would be keener. The better plan from the safety point of view would be to bring the foreshift deputies down the pit two hours in advance of the men and to keep the report book at the meeting station, so that it can be written up very shortly after the inspection has been made and so that it would be easily accessible to the workmen, duplicate reports being brought or sent out to the surface. This is the system adopted at many well-managed collieries, and it answers satisfactorily in every respect.

According to Special Rule 67 of the code in use in Cumberland in respect of the deputy, it states that "he shall travel from time to time such air courses as the Manager and Under-Manager may direct." The deputies at the Wellington pit did not periodically travel the return airway from their particular district outbye or inbye, though it is certainly desirable that the deputies at all mines should be well acquainted with all the main roads of the mine in which they work.

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* That there had been an improvement in the ventilation of the mine is evidenced by the figures taken from the ventilation book kept by the assistant general manager. Thus I find the following :—

Place of	Measured		Measured
measurement	January 27, 1908		October 22, 1909
	Cubic feet		Cubic feet
	per minute		per minute
Arch. Pit bottom intake	51,326		53,100
Infidel drift	26,702		34,400
Benks' Brow	24,756		27,200
At fault, going into 3rd North	10,243	at high air-crossing at in-bye side of 3rd North	15,600
Bottom of upcast	77,961		85,750