Complex sentence: Durand was the director of the mechanical engineering department and acting director of the electrical engineering department until he recruited H. J. Ryan from Cornell, a position Ryan held from 1905 until his death in 1934.
Split into simpler sentences: Durand was the director of the mechanical engineering department and acting director of the electrical engineering department. Durand recruited H. J. Ryan from Cornell to be director of electrical engineering, a position Ryan held from 1905 until his death in 1934.