Saving the rainforest is great in principle - but what if to do it, you face driving a 10-mile road through the very forest you're trying to save? That was the dilemma facing conservationists at Loch Arkaig in the West Highlands, who wanted to extract non-native trees planted 70 years ago. However, with a bit of thinking outside the box and some canny engineering skills they built a very special barge to ship out the lumber and leave the forest undisturbed. Richard Baynes took a trip on it to find out more.