From chapter XIV of The Mill on the Floss by George Eliot:
When Maggie was gone to sleep, Stephen, weary too with his unaccustomed amount of rowing, and with the intense inward life of the last twelve hours, but too restless to sleep, walked and lounged about the deck with his cigar far on into midnight, not seeing the dark water, hardly conscious there were stars, living only in the near and distant future. At last fatigue conquered restlessness, and he rolled himself up in a piece of tarpaulin on the deck near Maggie’s feet.
She had been sleeping for six hours before the faintest hint of a midsummer daybreak was discernible. She awoke from the vivid dreaming which makes the margin of our deeper rest. She was in a boat on the wide water with Stephen, and in the gathering darkness something like a star appeared, that grew and grew till they saw it was the Virgin seated in St Ogg’s boat, and it came nearer and nearer, till they saw the Virgin was Lucy and the boatman was Philip,—no, not Philip, but her brother, who rowed past without looking at her; and she rose to stretch out her arms and call to him, and their own boat turned over with the movement, and they began to sink, till with one spasm of dread she seemed to awake, and find she was a child again in the parlour at evening twilight, and Tom was not really angry. From the soothed sense of that false waking she passed to the real waking,—to the plash of water against the vessel, and the sound of a footstep on the deck, and the awful starlit sky.
What does "makes the margin of our deeper rest" mean? I am also ensure whether "before the faintest hint of a midsummer daybreak was discernible" means that it is still quite early before the sun rises.
