This is available in hardback from amazon for about £8.50. A Kindle edition is also available, and I daresay a paperback will be along in due course.

Nineteenth century true crime is very popular at the moment, probably due to the success of The Suspicions of Mr Whicher. The author of this book is American, so probably not consciously cashing in on that trend, but it might account for the slightly clumsy, slightly whimsical title. It isn't clear whether 'the killer of little shepherds' was a nickname given to the killer at the time or one dreamed up here. This is kind of a minor point, and doesn't detract from the book itself, but it did irritate me slightly.

The book gives an account of a French serial killer of the 1890s, Joseph Vacher. He murdered at least eleven people over a number of years, the majority being adolescent farm-workers. Vacher was a vagabond, and by committing his crimes over a vast geographical area, he evaded capture for a long time - no two crimes were investigated by the same people, and it took years for anyone to realise that there were links. The book also details the development of forensic science during the period, with Alexandre Lacassagne of Lyon pioneering techniques in autopsies which advanced the art of criminal investigation immeasurably. A celebrity in his day, Lacassagne was eventually called upon as an expert witness at Vacher's trial, to establish whether the defendant was insane, and whether he would therefore face life in a poorly guarded asylum, or public execution by guillotine.

Vacher was a vile character. Although inevitably the only accounts of him which survive are coloured by his notoriety, he really looked the part of the sinister outsider - a hunched, brooding tramp with a black beard, facial scars and an ear forever dripping pus, usually seen with a sack on his back. He almost feels folkloric, a kind of anti-Father-Christmas. But he deserved all the hatred and fear; his victims were savagely attacked, mutilated in horrifying ways, and frequently raped as they died (he killed boys and girls, favouring anal rape in all cases). Clearly this puts him more in Jack the Ripper's league than the usually run-of-the-mill Victorian murder cases, which seem positively genteel by comparison. Vacher had been in the army, and had served time in an asylum for shooting a woman who spurned his advances. All accounts suggest that he had a terrifying, monumental sense of his own entitlement, and was incapable of seeing anyone else's point of view.

It isn't a book for the faint-hearted. The details of mutilations on Vacher's victims are sometimes a bit light, possibly because those details aren't available. But at the same time as laying out the facts of Vacher's career, it also describes how forensic medicine at the time was carried out, in gut wrenching detail. Particular emphasis is given to the lack of hygiene - surgeons didn't have masks or rubber gloves to protect them - and the descriptions of smells, of putrefaction, and of (for instance) how they would examine the rectums of cadavers are a little gruelling. But as with so many fields of science in the Nineteenth Century, huge leaps forward were made due to the work of Lacassagne and his colleagues.

The book alternates chapters, giving us a look at what Vacher was up to (generally killing people) followed by a chapter on forensics. This works fairly well. The Vacher parts are probably more interesting, just because they're nastier, but it would probably be too much to just read them all one after another without anything to break them up. The chapters about forensic history cover a lot of ground, and are perhaps there to justify the book's existence, as otherwise we'd be left with a rather lurid and unpleasant murder case and nothing else.

But the book demonstrates nicely how important accurate medical knowledge was in solving crime, often amusingly ("...a woman named Adèle Bernard was imprisoned for having an abortion. After three months in jail, she gave birth to a child. The court released her.") It also goes briefly into various theories about people's criminality being evident in their facial features, a discredited idea that has an unpleasantly racist tinge. It does allow for an amusing anecdote about various eminent professors squabbling over whether a skull of a famous murderess showed any signs of criminality, but it's the kind of thing that fed into Nazi racial profiling.

Understanding the deficiencies in medical and forensic knowledge, and the difficulties faced by the French authorities in investigating crimes out in the rural areas, gives useful background in explaining how Vacher could have got away with it for so long. And the book leads up to the big confrontation between Vacher and Lacassagne in court - except that there wasn't really a confrontation, just a scientific professional giving evidence and a man trying increasingly desperately to act like he was mad to save his own neck. I guess history doesn't give us endings like in the movies.

If it feels a bit anti-climactic, that's not the author's fault, and there's a good description of Vacher's execution. I was surprised to learn they still executed people publically in France so late - apparently they continued to do so well into the Twentieth Century. It's odd that Vacher isn't better known. He lacks the mystery of Jack the Ripper, to whom he was inevitably compared, but he's faded into obscurity compared to serial killers operating not much later.

The book is well written, cracking along like a novel, and not throwing irrelevant information at us. It felt slightly patronising that the author told us how to pronounce some of the French names, but maybe they're not taught that kind of thing in America. There are a few pictures (not too gruesome). Happily, I didn't notice many typos, although the dust jacket blurb gives Vacher a circumflex accent he doesn't have in the book itself (Vâcher).

This is a good little book for a bit of gruesome light reading - I got through it in a day without really straining myself. Recommended for fans of true crime, but be sure you're happy with dark subject matter.