10 o'clock sharp
`` I 'd forgotten , sir , '' said Frank . Lord Hastings scribbled rapidly on a piece of paper , which he passed to Jack . `` This will fix you up , '' he said . `` Now remember , 10 o'clock sharp . '' The boys nodded their understanding of this order , saluted and left . Getting their things together , they hurried to the river , where Lord Hastings kept his motorboat ; and an hour and a half later they were proceeding slowly down the river . `` Guess none of the enemy will ever get in here , '' declared Frank , after a careful survey of the river .