I love this Mr. Thayer, in captain's hat and suit, holding what looks to be a cigar in one hand and pole in the other, with the shoreline behind him. Thayer is a well-known name in these parts, and it may be this is William G. Thayer--an educator and Episcopalian minister who built a second home and summered in Ipswich (son of Robert Helyer Thayer, a hardware merchant and ship chandler, and Hannah Appleton)--and that he is posing at Crane Beach in Ipswich.
The cyanotype is dated June 19, 1898 on the reverse and was presumably given to Mr. Thayer by a J.A. Small. It's in great antique condition. 4"x5" as mounted.