midnight
`` We 'll hit water pretty soon ! '' Crowley 's voice broke hours of silence , for they were sparing of language . They neither whistled nor sang nor spoke , for Man is a potential body from which his store of energy wastes through tiny unheeded ways . True to prophecy , in the darkness of midnight they walked out upon a thin skin of newly frozen ice . `` Look out for the overflow ! She froze since dark , '' Crowley cautioned . `` We 're liable to go through . ''