The John-Henry pit was sunk to the Main coal-seam, 312 feet deep, about 62 years ago.

The Main and Five-quarter coal-seams were worked from this shaft until 1877, when they were abandoned, the seams being nearly exhausted. Since that time, the shaft has only been used as a pumping-station for the purpose of draining these seams ; this being effected by means of a Cornish pumping-engine, with a cylinder, 72 inches in diameter and 8 feet stroke, working a bucket-lift, 21 inches in diameter.

In course of working eastward in the Brockwell seam, from the Harry pit, a fault was encountered, throwing the seams down to the east, from 270 to 300 feet. A considerable distance was driven beyond this fault in the Harvey seam, which was found on nearly the same level as the Brockwell seam.

About 3 years ago, it was decided to sink the John-Henry shaft down to the Hutton seam, by means if which the Hutton and Low Main seams would be won, and could be worked, on the west or rise side of the fault, and the Main and Five-quarter coal-seams on the dowthrow side.

The shaft being only 12 feet in diameter, there was not room to put in cages sufficiently large to admit of 2 tubs being drawn on one deck and still to retain the old pumping arrangement and it was necessary that some other system of pumping should be adopted, in order that the shaft should be left clear for coal-drawing.

There were three methods by which this could have been done :

(1) A direct-acting steam-pump could have been placed in the Main coal-seam ; (2) a large air-compressing plant could have been placed on the surface at the John-Henry pit, with pumps, worked by compressed air in the Main coal-seam ; or (3) an electric generating-plant could be placed at the Harry pit about ½ mile distant, and the current carried by cables to pumps placed in the Main coal-seam.

The first scheme was objectionable for several reasons :— The chief being the necessity for erecting boilers of high pressure at the John-Henry pit, and owing to the upcast shaft being ½ mile distant, there would of necessity be great difficulty in dealing with the steam in seams with blue-metal roofs. The second scheme would also have involved a large outlay in air-compressing and boiler-plant at the John-Henry pit, and probably it would be less efficient in working than an electrically-driven plant.

The third scheme was adopted, and the following are the principal reasons which led to that decision — (1) The necessity of increasing the plant on the surface at the John-Henry pit was entirely avoided (2) by keeping the generating-plant at the Harry pit, where a large boiler-plant is already in existence, a great saving in coal is affected and at nights and weekends, when coal-drawing is not in operation, there is sufficient steam generated by the waste heat from the coke-ovens to drive the electric plant and (3) the concentration of the plant would allow of better and more efficient supervision, and reduction of wear-and-tear, by having all the electric plant driven by one thoroughly efficient and reliable engine.

The generating-plant and pumps are capable of pumping the whole of the water, at present met with in the seams, at nights ; and, so long as this is the case, very little steam beyond that produced by the coke-oven gases will be required. It is possible that a considerable increase of water may be encountered at the large fault, when it is reached in these seams and in that case it will only be necessary to erect an additional boiler. By driving the pumps night-and-day there will be no difficulty in dealing with 1,000 gallons of water per minute during the 24 hours, as well as running the coal-cutting machines, and the hauling in the Hutton seam, which will be driven by this plant.

The steam-engine, as well as the whole of the plant, is of strong and substantial make, and affords an ample margin of power. It has been working since January of this year, and has not, as yet given the slightest trouble.

The President (Mr. J. G. Weeks), in moving a vote of thanks to the owners for their kindness in allowing the members to visit the South Durham collieries, and to Mr. Fenwick Darling for his interesting paper, said that the erection of the new plant had been efficiently and economically carried out, and afforded an excellent example of the work of a skilful engineer.

Mr. Henry Lawrence seconded the resolution, which was cordially approved.