'An important room, this!' cried Mr Wonka, taking a bunch of keys from his pocket and slipping one into the keyhole of the door. 'This is the nerve centre of the whole factory, the heart of the whole business! And so beautiful! I insist upon my rooms being beautiful! I can't abide ugliness in factories! In we go, then! But do be careful, my dear children! Don't lose your heads! Don't get over-excited! Keep very calm!' Mr Wonka opened the door. Five children and nine grown-ups pushed their ways in — and oh, what an amazing sight it was that now met their eyes! They were looking down upon a lovely valley. There were green meadows on either side of the valley, and along the bottom of it there flowed a great brown river. What is more, there was a tremendous waterfall halfway along the river — a steep cliff over which the water curled and rolled in a solid sheet, and then went crashing down into a boiling churning whirlpool of froth and spray. Below the waterfall (and this was the most astonishing sight of all), a whole mass of enormous glass pipes were dangling down into the river from somewhere high up in the ceiling! They really were enormous, those pipes. There must have been a dozen of them at least, and they were sucking up the brownish muddy water from the river and carrying it away to goodness knows where. And because they were made of glass, you could see the liquid flowing and bubbling along inside them, and above the noise of the waterfall, you could hear the never-ending suck-suck-sucking sound of the pipes as they did their work.