Complex sentence: In 1854, on the outbreak of the Crimean War, he travelled directly to Sebastopol to work as a surgeon; he went on to assist in running the General Hospital at Balaclava.
Split into simpler sentences: In 1854, on the outbreak of the Crimean War, he travelled directly to Sebastopol to work as a surgeon. He went on to assist in running the General Hospital at Balaclava.