That old Dutch sea-dog Martinus Harinxma, narrator of de Hartog's The Commodore (1986), is pressed into service again, this time on land: his voyage of self-discovery (involving dowsing, psychometry and time-travel) alternates with the story of a fourth-century Roman army colonel in this two-track novel. Martinus is now in his mid-70s, unhappy about becoming an old fogy as he ponders T.S. Eliot's line "Old men ought to be explorers." He and wife Sylvia, driving across North America, happen upon a town hosting a convention of dowsers, and Sylvia prods him into using the dowser's pendulum to learn more about his hobby, the invasion of Britain by General Theodosius in 368 A.D. Once in England, Martinus quickly makes contact with an 80-year-old centurion, watching over his adopted son, the colonel Mellarius. (The reader knows that the centurion is a ghost, albeit an active one, Mellarius' housegod; Martinus accepts this conclusion only at the end.) So the sea dog turns explorer, tracking Mellarius's movements through question-and-answer sessions with the pendulum; what emerges is that though Mellarius was a seasoned professional, harrying a marauding Welsh tribe into committing mass suicide rather than surrender, he suffered from fastidium, or war-weariness, to such an extent that the centurion, ever the brutal warrior, withdrew his spiritual support, and the Emperor ordered him to fall on his sword. As these discoveries pile up, Martinus, with much nudging from Sylvia, is making unwelcome discoveries about himself and his own paternal shortcomings. These discoveries culminate in Martinus' acceptance that the centurion "was me, part of my soul" and that we live "surrounded by a vast world of miracle and mystery." A quirky novel that despite its exotic elements has an overall flatness, in part because the relationship between the ghost centurion and his colonel son has eluded dramatization, and in larger part because Martinus is a curmudgeonly bore whose development is unaffecting.