Pickands Mather & Co., Cleveland, Ohio, recently announced the appointment of John O. Greenwood as vice president-marine. Mr. Greenwood assumed his new duties following the retirement of David A. Groh.

Mr. Greenwood joined Pickands Mather in 1970 as an administrative assistant in the Marine Department. He was named assistant to the marine vice president in 1975 and assistant vice president-marine in 1980.

Mr. Greenwood is recognized as one of the leading authorities on the history of Great Lakes shipping. He has written many books dealing with the Lakes trade, including the annually published "Greenwood's Guide to Great Lakes Shipping" and the multivolumed series "Namesakes of the Lakes."