Scapegallows, by Carol Birch

There has never been a dull time for slang in the English language. A time traveller going back 200 years might miss everything that's gnarly and banging about our own world, but he could join a crowd of blowsabellas, bene-feakers, twiddle-poops and niffy-naffy fellows (slatterns, counterfeiters, sissies and time-wasters), order up a tiddly (drink), and, if so inclined, between sips he could admire the innkeeper's Newgate knockers (curly, oiled moustaches).

If the tiddly didn't turn out to be a wibble (a bad drink), the traveller might stay long enough to get into conversation with a scapegallows: a person who had been sentenced to hang but had managed to escape. It might even be the celebrated double scapegallows Margaret Catchpole, a convicted horse thief and smuggler's moll who evaded the noose twice, and whose unusually adventurous life is the subject of this new novel by Carol Birch.

Birch's Catchpole, a woman of verve and determination, would be stimulating company for a night out in any century. Born in Suffolk in 1762, she grew up on its bleak, smuggler-haunted coast. As a young woman, she found work as a servant in Ipswich for the poet Elizabeth Cobbold and her wealthy husband. She clung to this prized job for years, although her position was repeatedly compromised by her boyfriend, a dashing "free trader" named Will Laud.

Will was not a bad man, but he was "a rake and a charmer, a rambleaway", and a dangerous man to love. As a smuggler, he lived outside the law, brought genuinely bad friends to her employer's house, and often needed Margaret's help. It was on his account that she finally got into serious trouble. In 1797, hearing that he was imprisoned in Newgate, she promptly stole a horse from the Cobbolds and rode pell-mell to London, disguised as a boy, to try to free him. Before she had fulfilled her mission, she was caught, tried and sentenced to be hanged: the usual punishment for horse-thieving.

Birch vividly evokes the terror of this, but Margaret did not live in fear for long. The Cobbolds intervened to get the sentence commuted, first to transportation and then to a seven-year term in Ipswich Gaol. Margaret served three years of this before making a disastrous attempt to escape. Caught, she received another death sentence, then another commutation, and this time she did get shipped to Australia. She lived the rest of her life there, eventually becoming a respected colonial midwife.

Despite its title, the real drama of Scapegallows emerges not in the two reprieves, which were relatively straightforward, but in Margaret's long and doomed struggle to carve out a secure life for herself while staying loyal to the man she adored. She was also repeatedly undone by her own strength of character. Her willingness to rise to every challenge was what ruined her – from the mad ride to London to the prison break. In the end, her bravery even killed Will, the man she tried to protect. Being so courageous was a curse; so was her capacity for devotion. This mixture of qualities makes Margaret a compelling heroine.

Ultimately, the novel resolves itself into a redemption story, in which Margaret's sterling character provides the basis for her success in Australia. The narrative arc is not entirely unlike that of the published Victorian account on which it is chiefly based, a moralised fable which has Margaret supposedly redeemed by her "virtue". For Victorian virtue, Birch substitutes feistiness – a quality that we 21st-century readers happen to admire more.

Scapegallows may be more rooted in its author's century than its subject's, but it is an intelligent and gripping novel – and gnarly enough to make your knockers curl.

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