Shake well to restore bulk and air thoroughly

"What are you afraid of, dear child? Stay with me; if you will do all the work in the house properly, you shall be the better for it. Only you must take care to make my bed well, and shake it thoroughly till the feathers fly - for then there is snow on the earth. I am Mother Holle.

As the old woman spoke so kindly to her, the girl took courage and agreed to enter her service. She attended to everything to the satisfaction of her mistress, and always shook her bed so vigorously that the feathers flew about like snow flakes. So she had a pleasant life with her; never an angry word; and boiled or roast meat every day."

The Illustrated Fairy Tales of the Brothers Grimm by Jakob and Wilhelm Grimm
edited by R. Klanten & H. Hellige, Die Gestalten Verlag Berlin 2003, p. 68