Wigan Album

This set illustrates superbly why deep-mining subsidence causes more damage on the surface than might be expected. Old near-surface workings such as this, with little weight above, can remain stable for many years. However, if deep below, modern mining takes place, involving cutting out the whole coal seam, and letting the roof fall into the void behind the advancing long-wall face, then the hitherto stable working above are suddenly undermined - and the old working collapse in. As several seams were often exploited beneath one another, this could result in a quite dramatic level of subsidence on the surface.

Can someone with mining knolwedge please let us know what we are viewing in these photographs. i.e Is that arch the original working and is the post from the same era ?
Would the "pillars & voids" on the other photo be from older workings ?
What would be the approximate date for each method ?
Whats is the pipe for ?.
Thanks in advance.
ML

Alan, this completes an excellent series of pictures showing the old mineworkings. I will try to find a picture of the buildings which stood above this area immediately prior to the construction of the "New Baths"

I may be wrong but I'd say the arches would be a later addition probably at the time of discovery. This would be to secure the roof a bit more and to enable bricking up of the voids to occur. The workings are early I think pre 1800's possible pre 1700's, can't remember off the top of my head though, and would be pillar and stall workings. This picture would show the main haulage road. The brickwok is there as they shut the workings to most probably be grouted to reduce the risk of collapse. The size of pillars that could be left at that depth would only need to be very small 2 feet in by maybe 3 feet going up to maybe 4 feet square. The deeper the mine the bigger the pillars to the extent the pillars could 100+feet in size.