For a minute the men contemplated the seal with the large distinctive letter “B” in the center.
“Open the letter, sir,” Ferguson urged and Kent, his fingers fairly trembling, jerked and tore at the linen incased envelope; the flap ripped away and he opened the envelope—it was empty.
Instinctively the two men glanced down at the parquetry flooring; nothing but a thin coating of dust lay there, and Kent looked up and down the corridor; it was deserted.
“Do you recognize the handwriting?” asked Ferguson.
“No.” Kent regarded the envelope in bewilderment. “What shall we do?”
“Do? Call up the Dime Messenger Service and see where the envelope came from; but first come and see my prisoner.
“Your prisoner?” in profound astonishment.
“Yes. I caught him chasing up the hall after you,” explained Ferguson as they hurriedly retraced their steps. “I put handcuffs on him and then went to you. Ah, here's the light!”
“The light, yes; but where's your prisoner?” and Kent, who was a trifle in advance of his companion in reaching the dining room, stood aside to let Ferguson pass him.
The detective halted abruptly. The chair into which he had thrust his prisoner was vacant. The man had disappeared.