In April 1855, Bernard Whittingham (fl.1850), a captain of the Royal Engineers, set off from Hong Kong aboard H.M.S. Sibylle. He had volunteered to join an Allied squadron attempting 'to discover the progress of Russian aggrandisement in North-eastern Asia, and to ascertain how far the reports of her successful encroachment on the sea frontiers of China and Japan were true'. In the context of the Crimean War's Pacific theatre, he was also keen to see avenged the Royal Navy's defeat by the Russians at Petropavlovsk the previous year. Whittingham's notes, published in 1856, give a personal and uniquely British account of an understudied time and place with far-reaching influence on later events. The book is also a rich source of anecdotes, not least that relating to the capture of crew members of the ill-fated Russian frigate Diana.