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

They think him drunk , Jessica thought.
Leto lifted his water flagon, held it aloft where the suspensor, lights shot beams of reflection off it. "As a Chevalier of the Imperium, then," he said, "I give you a toast."
The others grasped their flagons, all eyes focused on the Duke. In the sudden stillness, a suspensor light drifted slightly in an errant breeze from the serving kitchen hallway. Shadows played across the Duke's hawk features.
"Here I am and here I remain!" he barked.
There was an abortive movement of flagons toward mouths—stopped as the Duke remained with arm upraised. "My toast is one of those maxims so dear to our hearts: 'Business makes progress! Fortune passes everywhere!' "
He sipped his water.
The others joined him. Questioning glances passed among them.
"Gurney!" the Duke called.
From an alcove at Leto's end of the room came Halleck's voice. "Here, my Lord."
"Give us a tune, Gurney."
A minor chord from the baliset floated out of the alcove. Servants began putting plates of food on the table at the Duke's gesture releasing them—roast desert hare in sauce cepeda, aplomage sirian, chukka under glass, coffee with melange (a rich cinnamon odor from the spice wafted across the table), a true pot-a-oie served with sparkling Caladan wine.
Still, the Duke remained standing.
As the guests waited, their attention torn between the dishes placed before them and the standing Duke, Leto said: "In olden times, it was the duty of the host to entertain his guests with his own talents." His knuckles turned white, so fiercely did he grip his water flagon. "I cannot sing, but I give you the words of Gurney's song. Consider it another toast—a toast to all who've died bringing us to this station."
An uncomfortable stirring sounded around the table.
Jessica lowered her gaze, glanced at the people seated nearest her—there was the round-faced water-shipper and his woman, the pale and austere Guild Bank representative (he seemed a whistle-faced scarecrow with his eyes fixed on Leto), the rugged and scar-faced Tuek, his blue-within-blue eyes downcast.
"Review, friends—troops long past review," the Duke intoned. "All to fate a weight of pains and dollars. Their spirits wear our silver collars. Review, friends—troops long past review: Each a dot of time without pretense or guile. With them passes the lure of fortune. Review, friends—troops long past review. When our time ends on its rictus smile, we'll pass the lure of fortune."
The Duke allowed his voice to trail off on the last line, took a deep drink from his water flagon, slammed it back onto the table. Water slopped over the brim onto the linen.
The others drank in embarrassed silence.
Again, the Duke lifted his water flagon, and this time emptied its remaining half onto the floor, knowing that the others around the table must do the same.
Jessica was first to follow his example.
There was a frozen moment before the others began emptying their flagons. Jessica saw how Paul, seated near his father, was studying the reactions around him. She found herself also fascinated by what her guests' actions revealed—especially among the women. This was clean, potable water, not something already cast away in a sopping towel. Reluctance to just discard it exposed itself in trembling hands, delayed reactions' nervous laughter . . . and violent obedience to the necessity. One woman dropped her flagon, looked the other way as her male companion recovered it.
Kynes, though, caught her attention most sharply. The planetotogist hesitated, then emptied his flagon into a container beneath his jacket. He smiled at Jessica as he caught her watching him, raised the empty flagon to her in a silent toast. He appeared completely unembarrassed by his action.
Halleck's music still wafted over the room, but it had come out of its minor key, lilting and lively now as though he were trying to lift the mood.
"Let the dinner commence," the Duke said, and sank into his chair.