 The two vessels were nearly identical since "Gripper" had not been able to keep up with "Hecla", and all the equipment was made to be entirely interchangeable.They had cork insulation, cork plugs for the portholes and an improved heating system, coal-burning stove, placed in the lowest deck to deal with cold and condensation.The men were issued better clothing and lemon juice was stored in kegs rather than glass bottles.