The Realm of Shells, by Sonia Overall

Connections to the past on Margate sands

For students of the early Victorian novel, Margate has a sinister significance. It was here, in September1840, that the insanity of Thackeray's wife Isabella declared itself. Picking up her three-year-old daughter Annie as they played on the sands, Isabella made a brief attempt to drag the girl into the sea. Annie could only bring herself to tell her father what happened many years later. By this time, her mother was long since lost in a sequestered, semi-autistic twilight that enveloped the last half century of her life.

The Kentish resort at which Sonia Overall's heroine Frances Newlove fetches up in early 1835 offers an equally ominous vista. The Newloves - serious Low Church parents, teenage daughters Lizzy and Mary, eight year-old Fanny and farouche brother Joshua - are come to open a school, or rather a brace of schools, as in addition to her husband's labours among the boy boarders Mama is booked to superintend a young ladies' establishment. Neighbours include choleric Captain Easter with his dislike of "Whiggish nonsense", and enticingly well-heeled Mr da Costa, while behind genteel house-fronts lurk rumours of lost treasures, absconding owners - and a suspicion that something lies buried beneath the back-garden chalk.

Brought to the reader both through Fanny's here-and-now reportage and more decorous letters to brother James, the life of the school is prey to subterfuge. Lizzy begins a covert dalliance with da Costa, using the missive-toting gardener's boy as intermediary. Scapegrace Joshua, meanwhile, discovers an ancient shell-encrusted grotto under the greensward.

Eventually communicated to awestruck but calculating papa, this discovery causes great excitement. Urged on by the equally calculating captain, Mr Newlove over-extends himself to buy the land and establish the "druidical temple" as an ill-fated tourist attraction.

The Realm of Shells' chief distinguishing mark is its hot pursuit of historical authenticity. Easter 1835, research reveals, really was celebrated on 19 April. Slang dictionaries have been plundered to supply pungent back-chat about "pedigree quillies" and "good for nothing nabbers", and the children skip to rhymes about "Queenie Queenie Caroline".

More problematic is the level at which the novel is pitched. The early sections, in which wide-eyed Fanny surveys her domain, sometimes read like one of the young person's adventures with which Penelope Lively began her career. There are Georgette Heyer-ish adhesions about dashing young bucks, secret engagements and New Year balls. Only towards the end, at which Fanny glimpses something very nasty in the woodshed, do the real themes of manipulation and betrayal move into the foreground and the novel's slight resemblance to L P Hartley's The Go Between become clear.

While Fanny's voice, full of onomatopoeic accounts of household noise and incident, is thoroughly engaging, some of the best things here - in particular the scenes in which Fanny teaches George the gardener's boy to read - are perhaps the least Victorian in character. It may be that Overall will eventually come to regard the 19th century as a constraint on her very considerable imagination.

D J Taylor's 'Kept' appears next month from Chatto