SILHOUETTED in thought, a visitor contemplates a view of Lake Windermere - part of an atmospheric exhibition inspired by an artist's travels throughout Britain which is now on display in the North-East. Painting with Acid is a selection of about 85 of 700 works by Norman Ackroyd. The exhibition, which runs until April 21 at Durham Art Gallery, includes the artist's travelling workbox and a short film on outdoor etching, and focuses on his work in the last ten years. Gallery spokesman Dennis Hardingham said: "Most of his drawings, paintings and etchings are done on the spot to capture the moment and mood of the scene, whether it be brooding hillsides, curtains of rain over sodden moorland or freezing seas swirling around mist-shrouded Scottish highlands. By working on site, he is able to capture and express his own feelings when first confronted by calm winter light or savage Atlantic seas."