"Like enough because he was sleeping like he was last night," Tobias rejoined promptly. "Nobody had to drug his tea. You always see Bill Purvis wanderin' around before folks go to bed. But who ever kept tabs on him after 'leven or twelve o'clock? I cal'late Bill rolled out of the hay this morning 'bout his usual time and found the bank robbed."
"I swanny!" murmured Ezra.
"It might be like you say, Tobias," agreed Mr. Compton.
"Yes. It might. Huh! What's this?"
The lightkeeper stooped and picked something out of the sand just under the forced window. It was a small, flat, gold penknife. There were a few gold links attached to one end. It had been torn from a watch chain.
"I give it as my opinion," murmured Tobias, "that it was scraped off as the feller worked his way in over that winder-sill. I reckon, Mr. Compton, here is a real clue."
"Huh!" muttered the doubting Ezra. "I don't believe Arad Thompson ever wore that dinky little thing."
"Oh, sugar!" exclaimed the amused lightkeeper. "I don't guess Arad was anywhere hereabout when the burglars crawled in at that window. And he never wore this here doo-dad on his watch chain, nohow."
He shook his head, staring at the penknife reflectively. He had seen that knife—or one much like it—before. In whose possession?
"Cal'late I better see Arad about this," he said finally. "When the perlice come to take holt on this case, Arad will want to give them all the help he can."