nine
o'clock
That idea met with rather a hearty reception . Within three minutes all six high school boys were lying between blankets again , composed for sleep . No more explosions came to disturb their slumbers , which were deep and broken only when at last Dick Prescott called out : `` Fellows , we 're regular Rip Van Winkles ! It 's half-past nine o'clock ! '' `` And we 've that lake mystery to solve today ! '' uttered Greg Holmes , leaping up . `` Now , I do n't know how it is going to hit the rest of you , '' remarked Tom Reade , as he put down his coffee cup at the end of the hasty breakfast , `` but I 'll confess that I 'm not wholly keen about solving the puzzle of the lake mystery . ''