From "Manual of Muad'Dib" by the Princess Irulan

All of a pattern , he thought. You can plumb us by our language—the precise and delicate delineations for ways to administer treacherous death. Will someone try chaumurky tonight—poison in the drink? Or will it be chaumas—poison in the food?
He shook his head.
Beside each plate on the long table stood a flagon of water. There was enough water along the table, the Duke estimated, to keep a poor Arrakeen family for more than a year.
Flanking the doorway in which he stood were broad laving basins of ornate yellow and green tile. Each basin had its rack of towels. It was the custom, the housekeeper had explained, for guests as they entered to dip their hands ceremoniously into a basin, slop several cups of water onto the floor, dry their hands on a towel and fling the towel into the growing puddle at the door. After the dinner, beggars gathered outside to get the water squeezings from the towels.
How typical of a Harkonnen fief , the Duke thought. Every degradation of the spirit that can be conceived . He took a deep breath, feeling rage tighten his stomach.
"The custom stops here!" he muttered.
He saw a serving woman—one of the old and gnarled ones the housekeeper had recommended—hovering at the doorway from the kitchen across from him. The Duke signaled with upraised hand. She moved out of the shadows, scurried around the table toward him, and he noted the leathery face, the blue-within-blue eyes.
"My Lord wishes?" She kept her head bowed, eyes shielded.
He gestured. "Have these basins and towels removed."
"But . . . Noble Born . . ." She looked up, mouth gaping.
"I know the custom!" he barked. "Take these basins to the front door. While we're eating and until we've finished, each beggar who calls may have a full cup of water. Understood?"
Her leathery face displayed a twisting of emotions: dismay, anger . . .
With sudden insight, Leto realized that she must have planned to sell the water squeezings from the foot-trampled towels, wringing a few coppers from the wretches who came to the door. Perhaps that also was a custom.
His face clouded, and he growled: "I'm posting a guard to see that my orders are carried out to the letter."
He whirled, strode back down the passage to the Great Hall. Memories rolled in his mind like the toothless mutterings of old women. He remembered open water and waves—days of grass instead of sand—dazed summers that had whipped past him like windstorm leaves.
All gone.
I'm getting old , he thought. I've felt the cold hand of my mortality. And in what? An old woman's greed .
In the Great Hall, the Lady Jessica was the center of a mixed group standing in front of the fireplace. An open blaze crackled there, casting flickers of orange light onto jewels and laces and costly fabrics. He recognized in the group a stillsuit manufacturer down from Carthag, an electronics equipment importer, a water-shipper whose summer mansion was near his polar-cap factory, a representative of the Guild Bank (lean and remote, that one), a dealer in replacement parts for spice mining equipment, a thin and hard-faced woman whose escort service for off-planet visitors reputedly operated as cover for various smuggling, spying, and blackmail operations.
Most of the women in the hall seemed cast from a specific type—decorative, precisely turned out, an odd mingling of untouchable sensuousness.
Even without her position as hostess, Jessica would have dominated the group, he thought. She wore no jewelry and had chosen warm colors—a long dress almost the shade of the open blaze, and an earth-brown band around her bronzed hair.
He realized she had done this to taunt him subtly, a reproof against his recent pose of coldness. She was well aware that he liked her best in these shades—that he saw her as a rustling of warm colors.
Nearby, more an outflanker than a member of the group, stood Duncan Idaho in glittering dress uniform, flat face unreadable, the curling black hair neatly combed. He had been summoned back from the Fremen and had his orders from Hawat—"Under pretext of guarding her, you will keep the Lady Jessica under constant surveillance ."
The Duke glanced around the room.
There was Paul in the corner surrounded by a fawning group of the younger Arrakeen richece, and, aloof among them, three officers of the House Troop. The Duke took particular note of the young women. What a catch a ducal heir would make. But Paul was treating all equally with an air of reserved nobility.