midnight
The terrible cold did not let up , however , and Johnson 's hands were slightly frost-bitten when they camped that night . Once more they stood guard , but this time it was under trying circumstances . For they were now in the open , protected only by the tent , and the time they had spent in the cave , where it was comparatively warm , made them wish again for its shelter . Shortly after midnight , when Fred , in accordance with the arrangements , roused Mr. Baxter to take his turn at guard duty , there sounded , off to the rear , long-drawn-out howls . At the sound the sled-dogs raised their muzzles in the air , until they were pointing at the flickering and shifting Northern Lights , and sent back an answer . `` Wolves ! '' exclaimed Mr. Baxter .