The ancestral line of Henry Straith Venn (1869-1908) was a weighty, chronicled one stocked almost entirely on the male side by distinguished, formidable, moralistic churchmen. Henry's great-uncle, John Venn, was the logician who introduced the 'Venn diagram', that pleasingly bulbous, promiscuous mathematical diagram. But the impression created by Henry Straith Venn's family history is one of purely, rigidly straight (or Straith) lines.

His great-great-grandfather, the famous Rev. Henry Venn (1725-1797), was descended 'from an unbroken succession of clergymen from the time of the Reformation' (ODNB). The Rev. Venn, one of the Clapham 'Saints', was a founding figure in the British abolitionist movement. He attacked Methodists for making 'the ground of their Assurance an inward fleeting instead of the faithfulness of Jehovah, the sensation of a fluctuating heart instead of the unchangeable promises of God'. The Venn family itself, in its unvarying names and starkly consistent beliefs, seemed to give an analogy on earth to the inflexible rightness and unchangingness of the God above Whom they worshipped so sedulously.

Henry Straith Venn's great-grandfather, the Rev. John Venn (1759-1813), was the first chair of the Church Missionary Society and the rector of Clapham, still in his time a centre of radical evangelicism and abolitionism: he was the 'spiritual guide' to many of the most eminent anti-slavery campaigners in the Clapham Sect. Henry Straith Venn's grandfather, the Rev. Henry Venn (1796-1873), was an Honorary Secretary of the Church Missionary Society in London for some 32 years. Henry Straith Venn's father was Rev. Henry Venn (1838-1923), an Honorary Canon of Canterbury. One of Henry Straith Venn's sisters was married to a vicar who became the Bishop of Lewes (another was married to a cartoonist with Punch).

There was only the occasional swerve in the linearity of Venn family traditions. Here was one. In 1888, at the age of 18, Henry Straith Venn went up to his father's old college, Gonville and Caius in Cambridge. He stayed a single term. Within a year, Henry Straith Venn, from motivations unknown, was to be found farming, far away from Clapham and Cambridge, in Alleghany County, Virginia. In 1906 he married Miss Maria Garnett, the daughter of a lawyer from Washington, DC. Less than a year and a half later, Henry Straight Venn, the great-great-grandson of the Rev. Henry Venn who had consorted with notables such as the Countess of Huntingdon and the Earl of Dartmouth, died in America at the age of 38.

Within six months, on July 1908, Maria Venn, his widow, gave birth to a boy, Henry Garnett Venn, a first and last child. As if Someone were intent on abolishing this whole errant Venn line, this touchingly human blemish on the family record, fatherless Henry Garnett Venn soon followed his progenitor into the bosom of God, dying three days after his birth, on 6 July 1908.

'What's the point of this?' you ask me. 'Why bother?'

I answer: 'What else should a writer do except remember as honestly as possible? All the theories and cases and interpretations and axioms -- unless they are grounded in the actual, they are virtually worthless. That's what I believe, even if it makes me a black sheep.'