Then another idea came to him.
"It's written on a typewriter!" he exclaimed. "I wonder if it could have been done by Mort Decker? Perhaps he is in trouble there with Muchmore. Maybe the man has him locked up. Had I better tell the authorities?"
Then, as he looked at the message again, he had a different thought.
"No, Mort couldn't have written it," he said to himself. "He knows how to work a typewriter, and he'd use capitals in the places where they belong. And, besides, this message isn't finished. Whoever wrote it had to stop before he was through. I wonder what the rest of that word is. 'Priso—' Maybe it's meant for 'poisoned' and it's spelled wrong. I wish—"
But the boy's thoughts were suddenly interrupted by a noise at a window over his head. Thinking the person who had thrown out the mysterious message was again about to open the shutters, Bert watched anxiously, but, instead, a window on the second floor opened and Mort Decker leaned out.
"Hello!" began Bert.
"Hush!" exclaimed Mort, placing his fingers over his lips as an additional signal of caution. "Get away from here, Bert; Mr. Muchmore is coming!"
"But," went on the boy, "I have—"
"Don't say a word. Hurry away. I'll try to see you to-night, at the barn. Go, before—"
He did not finish the sentence, but hurriedly shut the shutters, and closed the window. Bert took the hint, and glided into the woods, where he could not be observed. He gave one look back at the mysterious house, and once more he saw that the window, from which Mort had looked, was open. But the stenographer did not peer forth. Instead, the face of Muchmore appeared. The man looked around carefully, as if to see if anyone had been communicating with inmates of the house. Then, apparently satisfied, as he saw nothing suspicious, he pulled the shutters tightly together, and closed the window.