Hi Titty ,
We are talking at cross purposes.
In the book the BFG ( Big Friendly Giant) the character the BFG puts a large glass thing up to the window of sleeping children...to catch their dreams.
Here: Lovely article
time.com/4343386/roald-dahl-bfg-book-movie/
"The witch’s potion was a delicious concoction that my father made us every evening at bedtime, a combination of canned peaches or pears, milk, and a few drops of either red, green, or blue food coloring whizzed up in a blender to make a homemade milkshake-type drink. “The witches dropped it off at the doorstep five minutes ago,” my father would tell us with convincing authority, the same way he told us about our BFG who lived in a cave under the apple trees of our orchard right next to our house"
Everything was magical, even the witch balls that hung on clear fishing twine at different lengths and heights from our bedroom ceiling. “Witch balls” are beautiful, antique, fragile balls of all different colors. My father told us that they were to keep the bad witches away: “One look at her reflection in the witch ball and she’ll be scared to death and disappear faster than she arrived.” We were safe; we had so many mystical things around us. The Witches (good ones); the BFG; Fantastic Mr. Fox, who lived under the “witch tree,” a spectacular beech tree that had grown from three small trees into one massive climbing tree, which stood gracefully halfway up the little country lane where we lived, in a rambling farmhouse called Gipsy House.
He did this to make sure that later the BFG could get his stick through to blow dreams into our room. Then my father kissed us good night, tucked us in snugly, and turned out our light. Then we waited . . .
The wait was never long. Usually within about five minutes a long bamboo stick slowly poked its way through the middle of our curtains. First the stick would aim at my older sister Ophelia’s bed. It stopped steadily for a moment, and then we would hear two terrifically loud blows, rather like the sound a great big whale makes when it blows through its spout. Then, very slowly and carefully, the bamboo stick would turn toward me. The thrill was exhilarating: what could be my dream tonight? Two huge blows were exhaled in my direction, and then the long bamboo would slowly retract back through the curtains, and within seconds we went to sleep. We couldn’t wait to go to sleep and dream our special dreams that the BFG had made for us that day, from his cave under the apple trees of our orchard.