Jonathan Cape, London, 1965, 24^th impression.  Hard cover, 351 pages.  Green boards with gold lettering on spine; light edge wear; spine ends lightly pushed; binding sound with a bit of a back lean.  A few age spots on outer page block; no jacket.  Map end papers; interior clean and unmarked with black & white illustrations.  ‘… the Walker family has come to Harwich to wait for Commander Walker’s return.  As usual, the children can’t stay away from boats, and this time they meet young Jim Brading, skipper of the well-found sloop Goblin.  But fun turns to high drama when the anchor drags, and the four young sailors find themselves drifting out to sea – sweeping across to Holland in the midst of a full gale!’ (from Goodreads)