Complex sentence: The completion of the Erie Canal in 1825 was an economic boon to the city, and a dam on the Chuctenunda River, finished in 1875, allowed the city to become an important manufacturing area, primarily of carpets.
Split into simpler sentences: The completion of the Erie Canal in 1825 was an economic boon to the city. A dam on the Chuctenunda River, finished in 1875, allowed the city to become an important manufacturing area, primarily of carpets.