The fan drift was a tunnel connected to the South upcast shaft at a depth of ? 30 yds which ran to the ventilation fan houses 50 yd. away to the south-west.

The fan houses were slightly off-line with the shaft axis but it’s not clear yet whether the fan drift at the shaft was in-line or came in obliquely.

The fan drift forked near to the fan-houses and ended in vertical shafts beneath each fan inlet.  During the 1950s modernisation, the main fan-house was completely reconstructed to create an air- reversing inlet several yards closer to the shaft.

Between 1915 and 1955 there appears to have been another ventilation fan located closer to the South shaft which would have had its inlet directly above the top of the fan drift.  The rim of the shaft connecting with the drift was constructed of bull-nosed bricks and could still be seen in-situ in 2010.  The bricks have since disappeared!