Shackleton selected the boat party: himself, Worsley, Crean, McNish, and sailors John Vincent and Timothy McCarthy. On instructions from Shackleton, McNish immediately set about adapting the "James Caird", improvising tools and materials. Wild was to be left in charge of the Elephant Island party, with instructions to make for Deception Island the following spring should Shackleton not return. Shackleton took supplies for only four weeks, knowing that if land had not been reached within that time the boat would be lost.