Finally Balthasar von Ulm leapt up from his stool, indicated with a flourish the glass globe, and proclaimed: “My Lords, My Ladies: the void.”

Heinrich said: “My father fell to his knees before the glass globe. Remarkable, he murmured. Miraculous. And here on Earth, right here on Earth! Children, come look, come see, Heinrich, Wilhelmina, Katharina, come look, the void, come see. Margaretha, come see. The scoffing sound my sister produced in response must have come from very deep in her throat, very deep indeed, Father! To express skepticism of that magnitude one must will the walls of one’s throat to bleed. And she said: There is no void, there is no vacuum, that sphere is filled with our atmosphere just as it was before. Tell me, Father, she said slowly, in a singsong, as one would address not a god,” said the Prince, “but a child, or a simpleton, what sensible distinction do you note? How exactly does the nothingness in that sphere make itself known, she asked, to your organs of sense?”

Their father, who now cocked his head and stared more quizzically into the glass globe, said nothing.

Herr von Ulm did not, however, as Margaretha (the astronomer surmised) must have expected that he would, and as he had done a decade ago, slink toward the door.