"I, sir? Certainly not! But this Isaac Boxtel, is he a thin, bald-headed, bow-legged, crook-backed, haggard-looking man?"

"You have described him exactly."

"He is the thief; he stole the black tulip from me."

"Well, go and find Mynheer Boxtel--he is at the White Swan Inn, and settle it with him." And with that the president took up his pen and went on writing, for he was busy over his report.

But Rosa still implored him, and while she was speaking the Prince of Orange entered the building. Rosa told everything, how she had received the bulb from the prisoner at Loewenstein, and how she had first seen the prisoner at The Hague. Then Boxtel was sent for. He was ready with his tale. The girl had plotted with her lover, the state prisoner, Cornelius van Baerle, and had stolen his--Boxtel's--black tulip, which he had unwisely mentioned. However, he had recovered it.

A thought struck Rosa.

"There were three bulbs. What has become of the others?" she asked.

"One failed, the second produced the black tulip, and the third is at home at Dordrecht," said Boxtel uneasily.

"You lie; it is here!" cried Rosa. And she drew from her bosom the third bulb, still wrapped in the same paper Van Baerle had so hastily put round the bulbs on his flight. "Take it, my lord," she said, handing it to the prince. And then, glancing at the paper for the first time, she added, "Oh, my lord, read this!"

William passed the third bulb to the president, and read the paper carefully. It was Cornelius de Witt's letter to his godson, exhorting him to burn the packet without opening it. It was the proof of Van Baerle's innocence and of his ownership of the bulbs.