How we met: George Parsonage and Alex Gray

Alex Gray 56, is a crime writer living in Bishopton by the River Clyde. She taught English until 1992, when she retired after being diagnosed with ME. The Riverman, Gray's fourth novel in her series about a detective called Lorimer, features the real-life character of George Parsonage, a lifeboatman who works on the Clyde.

When I was thinking about my next book, I envisaged one of the victims being fished out of the river. I like to research my books by going out and speaking to people. I could have looked up George Parsonage in the library archives - there's been so much written about him over the years - but I thought, "I've got to meet him." A good friend in my writers' group was a good friend of George's sister, so I asked whether I could have his number.

I'll never forget the day I met George. It must be two years ago, now. When I got to the house, he wasn't in - I think he was down at the boat shed - but he was expecting me. So I was taken through to this very sunny conservatory where there was an enormous rowing machine.

One of the things that Lorimer, my detective, does, is he looks around people's houses to get an idea of their character. I do that too - it's terrible, I know. But I loved looking round George's house.

In his garden, he has loads of flowerpots. I thought, "Great, this man's a gardener, too." It turned out George had rescued all these pots from the river and filled them full of flowers. It was paradise there.

Inside, I was astonished to see masses of paintings. What I didn't know then, was that George had been to the Glasgow School of Art and was an artist and art teacher. I was fascinated because art was my first love, and I set my first novel in the Glasgow art world.

He came in. Nothing prepares you for your first sight of George. He's got a shock of white hair, dark bushy eyebrows and twinkly blue eyes. But what really stands out about him is his fantastic toothy grin. He has more teeth than anybody I've ever seen.

What a welcome he gave me. Within 10 minutes we were pals, and it was as if we had always been pals. I'm not ultra-sophisticated, I don't bullshit, I don't skirt round a question. George is the same. I think he thought, "I could get on with this person."

The more I talked to him, over the months, the more he told me. I could phone him up anytime - maybe after months had gone by - and it was as if no time had passed in between. I still pop in and see him. One of the things we share is a love of weak tea.

When he read the start of the book there was a wee tear in his eye. "That's perfect, that's right, that's me," he said. I was delighted. He might not admit it but he had to get a hankie when he saw the dedication to the book, too. It reads: "To George Parsonage, Glasgow Humane Society Officer, to the memory of his father, Ben, and all the rivermen before them."

George Parsonage MBE, 63, has been rowing on the Clyde since before he can remember. He has been the riverman, rescuing people who get into trouble, since 1979 - when the previous riverman, his father Ben, died. George has saved more than 1,500 lives, and received the Royal Humane Society's Silver medal in 2005.

Alex first got in touch through a friend of my sister's. It didn't bother me being put in a book. I've given a lot of people a lot of help over the years with books and television and studies that they've been doing. I really didn't know Alex as a writer, then, so she was just another person. Although she did seem very nice.

In the past, some other people have written books about me. The most interesting is one that Bill Knox wrote called The Lazarus Widow, which featured a character called the riverman. Alex said to me that she didn't understand why someone wouldn't call a person by their real name. So she asked whether she could use my name in her book, and I said certainly.

Our first meeting was at my house. She wanted to know things about the river - how the river worked. She just asked lots of questions and I tried to help her the best I could. Subsequently, she sent me a chapter of the book, and I thought - this is fine. All the other books had me doing things that I would never do, but Alex got it just right. At the same time, I didn't know whether this was just somebody writing a book that would never see the light of day.

Over the weeks and months, we didn't meet that often, but she would maybe email or phone me with a question. We're very good friends now, no doubt about it. I've always been quite easy about passing things on. It's something I've grown up with. Since I was a youngster, the papers were always on at my father to answer questions.

My attitude towards passing on information is this: my father had an incredible knowledge of the river, which he passed on to me. Most of it is geared up toward safety. When someone gets into trouble, on the river, that's because a mistake has been made. And I thought, if one person reads Alex's book and gets an inkling about safety from it - that's success.

My wife, Stephanie, said to me the other day, "What if this book is absolute garbage? You'll go mental." I said "I will not go mental, because I gave Alex complete carte blanche." I thought, if she gets it wrong, she gets it wrong. Anyway, for all I know, there are a dozen people out there who are writing a book on somebody called George Parsonage. People just pluck names out of a hat, don't they?

I finished the book the other night. I don't usually get time to read, but I forced myself to do it, and I think it's absolutely fantastic - really exciting. I wasn't relieved when I read it, but I was very proud. I'm certainly planning to go to the book launch. s

'The Riverman' by Alex Gray is published in May by Sphere, priced £18.99