Complex sentence: John Scott, the owner of the colliery, was a London solicitor who had taken a lease of the property in 1816: he was unable to operate the pit profitably and pulled out in 1828.
Split into simpler sentences: John Scott, the owner of the colliery, was a London solicitor who had taken a lease of the property in 1816. Scott was unable to operate the pit profitably and pulled out in 1828.