How happy he whose toil
Has o'er his languid pow'rless limbs diffus'd
A pleasing lassitude; he not in vain
Invokes the gentle Deity of dreams.
His pow'rs the most voluptuously dissolve
In soft repose; on him the balmy dews
Of Sleep with double nutriment descend.

Book III, line 385. - The Art of Preserving Health (1744)