Complex sentence: In addition to the town, Halliday also named one of his steamboats the "William P. Halliday", it was under the command of Sobieski Jolly and was mentioned in Mark Twain's papers.
Split into simpler sentences: In addition to the town, Halliday also named one of his steamboats the "William P. Halliday". It was under the command of Sobieski Jolly and was mentioned in Mark Twain's papers.