about four o'clock
`` Exactly how wonderful you 'll never know . '' Then I lifted her up in my arms , and we went out of the cabin into the cool darkness of the night . `` I 'll row myself ashore , '' I said , `` and leave the dinghy on the beach . I shall be back about four o'clock , if that 's not too early for you . We ought to get our explosion over before there 's any one about . '' Joyce nodded . `` I do n't mind how early you come .