His last book was a biography of a great fellow writer of boys ' stories , George Alfred Henty .
Fenn and his family lived at Syon Lodge , Isleworth , Middlesex , where he built up a library of 25,000 volumes and took up telescope making .
Fenn 's last book was a biography of a great fellow writer of boys ' stories , George Alfred Henty .
Fenn and his family lived at Syon Lodge , Isleworth , Middlesex , where he built up a library of 25,000 volumes and took up telescope making .