"They had, indeed—an officer's party was destroyed or made prisoners."
"Are you sure of that?" persisted the man on horseback.
"I was an unwilling spectator of the battle!" said Frank.
"Unwilling! Were not you engaged in it?"
"Certainly not," he answered, a little nettled at the man's tone. "I was held a prisoner by the King's officer!"
"On what suspicion? And who and what are you?"
"I really do not know, sir," said Frank, growing quickly angry, "why I should answer so many questions put to me by a stranger. I ask you no questions as to your business here, and you will oblige me by making no inquiries as to mine."
But a new voice struck in, in tones which made every nerve in the young man's body tingle.
"Mr. Francis Osbaldistone," it said, "should not whistle his favourite airs when he wishes to remain undiscovered."
And Diana Vernon, for it was she, wrapped in a horseman's cloak, whistled in playful mimicry the second part of the tune, which had been on Frank's lips as they came up with him.