A Riddle

They were three robbers; aye,
And they robbed a red, red rose;
And they came from out the sky,
And they went where no man knows.

One came when the day was young,
And rent the curtain gray
Of mist that round her hung,
And he stole her pearls away;

One came when the day was old,
And a sable coat he wore,
And a belt of dusty gold,
And he robbed her treasure-store.

One came when the day was dead,
And no man saw him pass;
And he caught her petals red
And threw them upon the grass.

Three robbers bold were they,
And they robbed a red, red rose;
And they came and went away,
And whither—
no man knows.