Bedknob and Broomstick is a children's book written in 1957 by Mary Norton, who also wrote the books about the Borrowers.
The plot: some children are sent to stay with a lady, Miss Price, in the country during the London blitz of World War II. She is learning to be a witch, and enchants the brass knob of the children's bedpost. When you turn the knob, the bed travels to wherever you wish to be.
It is an excellent book rather like the better E. Nesbit stories.
Originally, it was published as two books; The Magic Bed-Knob and Bonfires and Broomsticks.
In 1971 it was made into a Disney movie, Bedknobs and Broomsticks.