Complex sentence: The second son of William Dallas of Lloyd's and Sarah Day, he was born in London 27 June 1809; he was descended from Alexander Dallas of Cantray, Inverness-shire.
Split into simpler sentences: The second son of William Dallas of Lloyd's and Sarah Day, he was born in London on 27 June 1809. He was descended from Alexander Dallas of Cantray, Inverness-shire.