Complex sentence: Fisk Street Station went into service October 2,1903, built by the predecessor to Commonwealth Edison, Chicago Edison Company, whose Chairman was Samuel Insull and Chief Engineer was Frederick Sargent.
Split into simpler sentences: Fisk Street Station went into service October 2,1903. It was built by the predecessor to Commonwealth Edison, Chicago Edison Company, whose Chairman was Samuel Insull and Chief Engineer was Frederick Sargent.