NAPOLEON did us a favour. His wars in the early 19th century curtailed travel in Europe and meant many British artists had to explore their own land for inspiration. Foremost among them was Joseph Mallord William Turner.

In his mid 30s, Turner, the London-born son of a Devon barber, toured the South West and in 1813 he came to the Tamar Valley. He remarked that he had 'never seen so many natural beauties in such a limited space of country'.

Almost 200 years on, one of Turner's most cherished paintings, 'Crossing The Brook', inspired two women who share a love of the landscape and history of the Tamar Valley to join forces in producing a book on the artist's work there.

But this is not just a book of artistic appreciation, it is also part detective story. The authors, former teachers Diana Cook and Dorothy Kirk, have painstakingly researched the detail of Turner's painting to identify surviving architectural witnesses of the original work – no mean feat, artists are prone to shift the scenery for greater effect.

The painting, with its idealised view of Newbridge, Gunnislake, shows in the foreground a girl seated on the right bank. Her companion has almost crossed to the other side — hence the title. It is, say the authors, an allegory of female puberty, the crossing of the divide between childhood and womanhood.

But the masterly, almost soft focus view down the valley, is not entirely romanticised. Huge blocks of granite are also in the foreground, anchoring the idealised landscape with an industrial realist reminder. It can be seen as another allegory — the transition from pastoral idyll to brute industry.

For Turner was aware that terrible poverty was just a short walk from every pastoral scene. Miners worked below the mineral-rich valley, their womenfolk above, sorting copper ore. The authors say that as late as the 1980s, they were remembered as the 'Amazon women'.

The book is replete with Turner's sketches, used by the authors to locate the same spot today – sketches and modern photographs provide a clear visual comparison spanning the centuries.

The authors' love of the artist's work and of the landscape he walked shines through the book. It can only encourage many more to discover the artistic and actual delights of the valley.

Diana Cook at the launch of the book at the Tamar Valley Centre in Drakewalls last Wednesday said 'Crossing The Brook' set them on a voyage of discovery that absorbed them for many years. 'The landscape revealed secrets to us,' she added.

Dorothy Kirk said it had been a 'great joy to walk in Turner's footsteps, singing the praises of the Tamar Valley, which enchanted Turner — and enchants us still'.

l 'Turner in the Tamar Valley' by Diana Cook and Dorothy Kirk is published by the Tamar Valley AONB, price £9.95. It is available from bookshops and the Tamar Valley Centre. An exhibition to mark the book's publication runs at the centre until December 23. See http://www.tamarvalley.org.uk">www.tamarvalley.org.uk or ring 01822 835030 for opening times.