Complex sentence: Thoms was an antiquary and miscellaneous writer, for many years a clerk in the secretary's office of Chelsea Hospital, was in 1845 appointed Clerk, and subsequently Deputy Librarian to the House of Lords.
Split into simpler sentences: Thoms was an antiquary and miscellaneous writer, for many years a clerk in the secretary's office of Chelsea Hospital. He was in 1845 appointed Clerk, and subsequently Deputy Librarian to the House of Lords.