Complex sentence: In addition to his own cargo vessels to serve his sugar refinery, he had investments in the Montreal Towboat Company plus he helped finance the Montreal Telegraph Company and the Montreal Fire Assurance Company, serving as a director of both companies.
Split into simpler sentences: In addition to his own cargo vessels to serve his sugar refinery, he had investments in the Montreal Towboat Company. He also helped finance the Montreal Telegraph Company and the Montreal Fire Assurance Company, serving as a director of both companies.