Complex sentence: The SER built a line from Purley to Kingswood railway station and further extended to Tattenham Corner railway station between 1897 and 1901, by the latter date it had become the South Eastern and Chatham Railway.
Split into simpler sentences: The SER built a line from Purley to Kingswood railway station, extended to Tattenham Corner railway station between 1897 and 1901. By the latter date it had become the South Eastern and Chatham Railway.