"I don't know," he answered childishly as he turned up the light.
There was a litter of papers strewn upon the office floor. A long table was piled with letters opened and unopened; there was a typewriter on a stand, a copying-press, a high desk with ledgers, and in a corner, suspended from hooks in the ceiling, the compound pendulum that Astro had described. On the horizontal shelf, fixed to the end of the pendulum, was a white card; and, extending from a table near by, an arm carrying a glass pen projected so that, when the pendulum was swung, a curve in purple ink was traced on the card. A heavy weight depended from the bottom of the instrument.
Hudson sunk into a chair and groaned. The girl waited without a word, watching him.
Then Valeska approached him. "Mr. Hudson," she said gently, "pray don't take it all so hard. I'm sure that you are innocent, and we'll both help you. If you tell us everything, we can find some way of saving you."
He raised his head and looked at Astro, who nodded in confirmation. Hudson took courage. "The first thing, the most important thing, of course, is to explain about Professor Dove's death. I have no idea how it occurred. Indeed, I didn't know he was dead until you told me. I suspected that something fatal had happened; but I knew nothing definite."
"When did you see him last?"
"Two weeks ago, but Miss Vivian has seen him since then."
The girl took it up. "It was here in this office that I saw him. He was intoxicated, and he frightened me;
