A. E. Housman

Morns abed and daylight slumber

Were not meant for man alive.

Clay lies still, but blood's a rover;

Breath's a ware that will not keep.

Up, lad: when the journey's over

There'll be time enough to sleep.

(From "Reveille," one of the 63 poems in his book,  A Shropshire Lad, which was published in 1896.)