midnight
`` How do you know we ca n't ? '' demanded Tommy . `` Because it 's dark , and because we know nothing about the country , '' replied Will . The boys sat before the fire until midnight listening for the return of their chum . When it began to snow they reluctantly decided that George had crawled into some temporary shelter for the night and would not think of trying to make his way home through the storm . `` You boys go to bed now , '' Will advised , `` and I 'll sit up and keep watch . If you hear me firing how and then , do n't think the camp 's been attacked .