Sometimes The Roof Is Safer On The Floor.

[The Old Ruminator]

Usual Tuesday larking about.

P7210055 - Copy by Nicholas Chipchase, on Flickr

P7210052 - Copy by Nicholas Chipchase, on Flickr

[pwhole]

Impressive. Was that all a flat-out crawl to begin with?

[The Old Ruminator]

Next time a photo of the roof actually on the floor. As ever more caving photos on the forum, please.

[Duck ditch]

It reminds me of a time when we were banging the roof off a sump.  I still cant get my head round Whether  we were just displacing the water upwards or not.   

[Fjell]

It looks like one the of the Bath stone mines on a very bad hair day.

Are you capping that keystone? You know, like with a hammer? Or are you on the end of a wire?

[The Old Ruminator]

A very long wire.

[Speleotron]

If the width of the sump was the same as the width of the roof then you were just raising the water level by an equal amount, probably making the sump harder as well as the rubble from the roof wouldn't pack 100% efficiently, so the floor of the sump would rise more than the ceiling of the passage, and hence the airspace would shrink. Of course, you can remove the rubble from the sump which was probably the point of the operation.

[mikem]

Unless the sump level was sat at or near the spill point, in which case the water would be displaced over the edge.