He is also the one who has so far had the longest continuous period of office, a not unconnected fact, and in addition he is one of the few politicians whose reputation went up after he left the top office: Arthur Balfour, President Truman and very few others are his companions in this select group. It never came." Jackson and Costello's term for this relationship is "consubstantiality". After his father's death, Joyce wrote to Harriet Weaver: "I was very fond of him always, being a sinner myself, and even liked his faults. Hundreds of pages and scores of characters in my books come from him." For that reason alone, quite apart from its expansion of what we know about the Joyce family, this book is abundantly justified.But if I were sipping a glass of porter in a cavernous Dublin boozer and John Stanislaus Joyce came through the swinging doors I rather think I should slip, deftly and unobtrusively, towards the nearest exit..

"He longed for a gesture of some understanding from him, his own flesh and blood, for the strange struggles and achievements of his life as a writer. "Ulysses is in many ways a book about failed fatherhood, but it took the author's own failed father to engender it," say the authors.Joyce kept on hoping for some sign of approval for his writing. But the two of them were also engaged in some search for the meaning of paternity, that complex pattern of resistance and reproduction implicit, if so often inarticulate, in the father- son relationship. "I often told Jim to go for the Bar, for he had a great flow of language and he speaks better than he writes," observed John Joyce at a time when his son was one of the most celebrated writers in the world.

"If that fellow was dropped in the middle of the Sahara he'd sit, begod, and make a map of it," his father once declared. The authors think this urban passion was "in many ways the most valuable bequest that James Joyce would ever receive".Their mutual love - which was not watered by many visits from James, who thought his father in Dublin lived "among savages" - was partly paternal admiration, apparently unrelated to the actual books his son wrote. In spite of an absence of any literary or intellectual meeting-point, both had a fondness for tales and song, a proud sense of the Joyce tradition (the magnificent portrait of John Joyce by Patrick J Tuohy reproduced on the book's cover hung prominently in James's Paris flat), and a love of wandering through, and cherishing the topographical minutiae of, the Dublin streets. filled with pictures and newspaper cuttings of James".A literal transcript of John Joyce's windy and self-aggrandising recollections to an anonymous interviewer who bearded him in his last years, with its "Begors" and its pub-swagger, is one of the key sources of this biography. There is also a corroborative account by another son, Charles, adding further details of his drunken prodigality.Although Jackson and Costello insist that "James Joyce is not the hidden subject of this biography", the relationship between Joyce pere et fils most certainly is, and makes for its importance. Transformed into fiction, his life is neatly epitomised in the Portrait as: "a medical student, an oarsman, a tenor, an amateur actor, a shouting politician, a small landlord, a small investor, a drinker, a good fellow, a storyteller, somebody's secretary, something in a distillery, a taxgatherer, a bankrupt and at present a praiser of his own past".The alternative view - expressed by his other son, Stanislaus, in My Brother's Keeper, an account which Jackson and Costello describe variously as "sour", "dogged" and "ungracious", and which their book is in some sense writing against - is of an improvident drunkard who dragged his wife and 16 children into poverty, squandering the Joyce patrimony of properties in Cork (the Joyces had been successful in trade), abusing his wife and neglecting all his children with the exception of his favourite son, "Jim", and ending his life, in the authors' words, "bedridden and toothless .. his decidedly odorous room ... If I am unconvinced of the "genius" of John Joyce, the importance to any understanding of the author of Ulysses, or the father-son relationship, is incontrovertible. The authors at first waver slightly between admitting frankly that John Joyce did nothing in the eyes of the world to justify a biography and making the ambitious claim that: "James's ebullient father was his prime inspiration and supplied the context (and often the text) to almost everything he ever wrote." Much depends on the reader's estimate of Joyce Senior's "mercurial charm", witnessed by those in Dublin who cherished the dapper figure in spats, monocle and waxed moustache, with his boisterous (and foul-mouthed) conversation, his fine tenor voice (the Joyces down the generations were addicted to music and song), and those tales of which he was invariably the hero.

It is to the credit of the joint authors of this thoroughly researched and fluently written biography that they make the best case possible for attending to John Joyce, who, if nothing else, was the original of Simon Dedalus in A Portrait of the Artist as a Young Man and of much in Leopold Bloom and H C Earwicker too. But the feckless Dublin bar-fly John Stanislaus Joyce, who seems not to have read any of his son's books from cover to cover, and whose favourite reading was not The Egoist or Transition but Tit-Bits, presents rather more of a challenge. But, apart from a few polemical broadsides, Thomas barely acknowledges other interpretations of this history. The Slave Trade is an old-fashioned exercise in story- telling, untainted by wider historical questions It is the worse for that.. Having once been laughed out of a publisher's office for proposing a life of Arthur Hugh Clough, I approached this biography of James Joyce's father in sardonic mood.

The spouse-of-genius genre needs no justification, with Ann Thwaite's Emily Tennyson, Paul Ferris's Caitlin Thomas and Brenda Maddox's Nora Joyce among its notable successes. Equally disappointing is Thomas's reluctance to engage directly with the arguments of more radical historians. The Slave Trade draws heavily on the archival work of other scholars. History written from a different viewpoint often helps clarify many issues. What is disappointing about Thomas's work, however, is his failure to place his narrative in historical perspective, to understand the slave trade not simply in terms of the personalities that were involved in it, but also in terms of the economic, social and political developments that helped shape it.