Complex sentence: The triangular cross-section of catenary used in the original electrification was only repeated by one other railway-the London, Brighton and South Coast Railway used a similar triangular catenary from 1909 until 1929.
Split into simpler sentences: The triangular cross-section of catenary used in the original electrification was only repeated by one other railway. The London, Brighton and South Coast Railway used a similar triangular catenary from 1909 until 1929.