Upon arriving in Ithaca, NY in the spring of 1828, Cornell first found work as a carpenter before being hired as a mechanic by Otis Eddy to work at his cotton mill on Cascadilla Creek. On Eddy's recommendation, Jeremiah S. Beebe then hired Cornell to repair and overhaul his plaster and flour mills on Fall Creek. During Cornell's long association with Beebe, he designed and built a tunnel for a new mill race on Fall Creek; a stone dam on Fall Creek, which formed Beebe Lake; and a new flour mill. By 1832, he was in charge of all Beebe's concerns at Fall Creek.