Lyon accompanied the second Parry expedition in search of a North West Passage as captain of Hecla (1821-23; Parry commanded the Fury). His Private Journal of the voyage supplemented Parry’s own, official account of the voyage. The expedition proved of importance for the successful co-operation between the Europeans and the Eskimo encountered; indeed, by the aid of a sketch map of the area Parry discovered a potential route from one of the Eskimo. Lyon observed closely the habits and character traits of the different tribes of Eskimo and the Private Journal offers an excellent description of them. Lyon sailed with Parry again in 1824, this time to attempt a crossing of the Melville Peninsula. Lyon’s narrative of the voyage as far as Wager Inlet and Repulse Bay contains information about Southampton island and the Eskimos of the region.