During the sinking, heavy feeders of water of up to 1000 gall/min (4546 ltr/min) were encountered  in the Magnesian Limestone and the upper sections of the Coal Measures strata. In order to overcome these feeders  the shafts were lined with  cast iron tubbing.  This  was of the “English” type with 10 segments per ring, secured by means of wooden wedges inserted between the back of the tubbing and the excavated shaft wall and with thin wood sheeting between the vertical and horizontal joints.  In the North shaft there were integral brackets and boxes cast-in to hold the timbers supporting the shaft guides.

Typical cast-iron English tubbing

In  1891 the manager, J.C.B. Hendy,  wrote:

‘The thickness of the tubbing is  ¾in, 1½in and 1¾in. The top segments  being 2ft 6in by 4ft 6in and the lower 2ft by 4ft 6in’.

The thicker sections would be used to cope with the increased water pressure as the depth increased. Whether they were arranged in this way between each wedging curb (a support ring acting as a water  barrier) or over the full depth of the tubbing is unclear.

Lip of South pit fan drift entrance

It was also stated, however, that, during sinking 350 galls/min of water were encountered at about this depth so it would seem possible that the fan drift depth was mis-reported.