Fact.

I'm a bit obsessive about detail. When I'm writing a story, I don't like to get factual details wrong. I will spend a lot of time on the internet while writing a story just ensuring that the things I'm putting into it are correct. It is terrible for a procrastinator like me because sometimes pursuing the correct detail (what colour exactly is a bar of Lifebouy soap? Precisely how long does it take to taxidermy a hamster? Can you buy top loading washing machines for doll's houses? When was the whetstone invented? Did people in 1917 have an awareness of natural satellites?) can lead you into the most fascinating tunnel of distractions and you find yourself an hour later a million miles away from the original small query.

Often the internet or reference books cannot readily and reliably answer your detail query. I have been writing a story set in 1917, in Arras on the front line. I managed to put together the bones of the story using the facts from a selection of books, archives, websites and general reading. But I had got to the point where I was reading through my complete story feeling a little anxious about fine detail. You hope people will read the story. You hope people will be absorbed by the tale and not trip over inaccuracies. You hope you haven't blundered rough shod over the truths of history and that you've been respectful to the real life event in the construction of your fiction. But with this story I've found the precision of certain detail hard to nail down.

I am really lucky to know an amazing writer who specialises in military history who was able to help me. Bryan Perrett has been writing historical fiction and non fiction for years. His work covers a wide range of military and naval warfare. If you have children, they will have read his books, in the Scholastic 'My Story' series, where specific historical events are told through the eyes of a young person. Bryan is brilliant at making history accessible, understandable, but most of all alive and very engaging.

We spent a lovely morning going through my story. Bryan highlighted historical inaccuracies and was able to add detail that I would never have thought about. I realised how even the most careful of internet research can let you down - I'd spent ages trying to pin down what sort of helmet soldiers in 1917 would wear, and I'd confidently called it a Brodie. This was not only wrong, but the character in my story, at rest in a trench dugout, would in fact be wearing his balaclava not his helmet (which would more often than not be placed protectively in his lap during rest periods.) And who knew that shells make a noise like tearing fabric... I'd sort of assumed it would be a whistling sound. It's the kind of detail that begins to capture a visceral reality. Bryan was able to help me with so many detailed points from army commands to war time church etiquette.

We spoke about prescience, too; an uncanny and surprisingly common phenomenon where people going into battle often have a particular sense when they will not make it back and remark upon it.

Many thanks to Bryan, for being such a brilliant historical consultant, for sharing my excitement in the story and for the sort of attention to detail that I love. And to all experts who help us writers with getting the details right and keeping things authentic.