Complex sentence: In 1835, he moved to the free state of Ohio, where he became a professor at Oberlin College; he served as its second president from 1851 to 1866.
Split into simpler sentences: In 1835, he moved to the free state of Ohio, where he became a professor at Oberlin College. After more than a decade, he was selected as its second president, serving from 1851 to 1866.