2500 of the 5000 miles that make up the Atlantic coast belong to Maine. With a former Bowdoin buddy, Morten Lund cruised the Maine Coast, returned with a log of ""a model maine Cruise."" His boat was the powered puff. Lund remarks upon the passing scene and inhabitants--Old Orchard ""an outstanding piece of Pop Art,"" Prout's neck and Winslow Homer, lobstermen, and on the boating life with its elementals--Scotch neat, lobster from the pot, outwitting fog and finding a good anchorage. Casual, companionable--and undemanding pleasure trip for Maine and boating enthusiasts.