 Snow vehicles did not yet exist however, and so his engineer Reginald Skelton developed the idea of a caterpillar track for snow surfaces.In the middle of 1909 Scott realised that motors were unlikely to get him all the way to the Pole, and decided additionally to take horses (based on Shackleton's near success in attaining the Pole, using ponies), and dogs and skis after consultation with Nansen during trials of the motors in Norway in March 1910.Man-hauling would still be needed on the Polar Plateau, on the assumption that motors and animals could not ascend the crevassed Beardmore Glacier.