MARBLEHEAD – One of the mainstays of the Marblehead Historical Commission is stepping down.Retired dentist and Tufts professor Dr. Raymond Cole Jr., a Navy veteran of World War II and the Korean War who rose to the rank of lieutenant commander, has resigned from the commission due to what his son Kenneth Cole called “health issues.”Selectmen read Cole’s letter last week and voted to accept his resignation, send him a letter thanking him for his service and naming him a commission member emeritus.The rare honor recognizes Cole’s longtime service to history in the town Marbleheaders call the birthplace of the American Navy.Most recently Cole donated a roomful of sea-going memorabilia to serve as the Marblehead Maritime Museum at Abbot Hall, telling the story of Marblehead’s contributions to fishing and yachting as well as the Navy and Merchant Marines. The dedication 18 months ago attracted so large a crowd that some of the ceremonies were moved to the selectmen’s meeting room.The start-up contents of the museum comprised Cole’s collection of maritime memorabilia. He also donated $250,000 for the upkeep of the museum room.The collection includes a number of paintings of ships named for Marblehead and its historic figures, created on commission by Marblehead artist Samuel Hanks Bryant, an illustrator for Houghton Mifflin Publishing Co. for years. His work appears in several of C.S. Forester’s books about the fictional exploits of 19th Century British naval hero Horatio Hornblower.Born in 1921 at the Mary Alley Hospital, Cole is a Marblehead High and Tufts University graduate who has served as the director of several local banks in addition to his dental and academic careers. He has also written several books about Marblehead.