Complex sentence: He was afterwards assistant physician at the Children's hospital, Great Ormond Street, and physician at the Great Northern hospital, lung disease forcing him to retiring in 1882; and from that point he devoted himself to writing and literary research.
Split into simpler sentences: He was afterwards assistant physician at the Great Ormond Street Hospital for Children and physician at the Great Northern Hospital. Lung disease forced him to retire in 1882, and from that point on he devoted himself to writing and literary research.