 During the war Chatwin and his mother stayed at the home of his paternal grandparents , who had a curiosity cabinet that fascinated him . Among the items it contained was a " piece of brontosaurus " ( actually a mylodon , a giant sloth ) , which had been sent to Chatwin 's grandmother by her cousin Charles Milward . Travelling in Patagonia , Milward had discovered the remains of a giant sloth , which he later sold to the British Museum . He sent his cousin a piece of the animal 's skin , and members of the family mistakenly referred to it as a " piece of brontosaurus . " The skin was later lost but it inspired Chatwin decades later to visit and write about Patagonia . 
