Mason & Dixon return to London, where they decline, for various possible reasons, to accept another assignment together. Dixon is sent to the North Cape, Norway to observe the return Transit of Venus, while Mason is sent to Ireland to do the same. There, he is conscripted into helping deal with a peat-flow, given to temperamental behavior, and visited again by Rebekah. Upon his return to London he argues with Maskelyne, who assures him their office is no longer what it once was, and accepts another assignment to travel to Scotland.