midnight
Of course , with so many who really belonged in the camp , tramping around it , there was little likelihood of an alien foot being discovered . Nevertheless , Bud hoped for something of this sort . But it was not to be . No trace of the midnight intruder , who had left the ominous warning , was discovered . And yet he had come and gone -- had even penetrated to the tent where the boys were sleeping . `` It 's either bluff , or it means something , '' declared Bud , as they assembled for lunch . `` And if it is n't bluff , but a _ fight _ , Hank Fisher and Del Pinzo will find we can stick to our guns as well as they ! ''