Stapleton led me along a narrow path across a wide, flat part of the moor. The land around us was a strange, green colour. We walked towards a hill of grey rock.
'Be very careful, Dr Watson,' said Stapleton. 'Stay on the path. We are in the Great Grimpen Mire. There is a sea of soft mud underneath the grass. If you fall in, you will never get out again.'
'Thank you for telling me,' I said. 'But why do you live here? It is a dangerous and lonely place.'
'I am a naturalist. I study nature,' said Stapletoon. 'There are many interesting flowers and birds on the Great Grimpen Mire. And there are some unusual animals on Dartmoor.'
At that moment we heard a strange sound. It was a deep howling sound-the sound of a large dog. It came from some distance away.
'Stapleton! Is that the sound of a dog?' I asked.
'It is only the sound of the wind.' said Stapleton. 'The wind blows through the rocks and makes strange sounds. But here is my house-Merripit House on the moor. 'He pointed to the long. low farmhouse which we could see near the hill. 'And my sister is coming to meet us.'