Complex sentence: This was only short lived as the South Devon Railway was in turn amalgamated into the Great Western Railway on 1 February 1876, which in turn was nationalised into British Railways in 1948.
Split into simpler sentences: This was only short lived as the South Devon Railway was in turn amalgamated into the Great Western Railway on 1 February 1876. The Great Western Railway was nationalised into British Railways in 1948.