Complex sentence: The new works was built on the site of the station of the Garnkirk and Glasgow Railway which the Caledonian had absorbed, near to the chemical works of Charles Tennant and was named after the nearby parish church of St. Roche.
Split into simpler sentences: The new works was built on the site of the station of the Garnkirk and Glasgow Railway (which the Caledonian had absorbed) near to the chemical works of Charles Tennant. It was named after the nearby parish church of St. Roche.