about ten o'clock in the morning
`` Wake up , Frank ! '' Frank , roughly shaken by Bob Upton , sat up in bed . He rubbed his eyes drowsily , and for a moment all the strange happenings of the previous night seemed like some dream . Then Frank recalled reaching the school about ten o'clock in the morning , when all the students were in their classes , of reaching his room unobserved , lying down on his bed in his clothes to rest and collect his thoughts , and of dropping into a nap . `` I say , '' hailed Bob excitedly , `` where in the world have you been ? '' `` It 's a long story , '' explained Frank with a prodigious yawn and stretching himself . `` You would n't believe it if I told it to you .