Complex sentence: They ran on Brunel gauge track to make it easier to drop rock from the wagons between the rails, which were run out to sea on a timber framework, a method of construction that was perfected by Sir John Coode.
Split into simpler sentences: They ran on Brunel gauge track to make it easier to drop rock from the wagons between the rails. The construction track was run out to sea on a timber framework, a method of construction that was perfected by Sir John Coode.