“These messages will be written in a special ink, Burke. You will reply in kind. A bottle of the ink is on your desk, where I placed it.
“Each word in every message will be written backward. You will write your words backward when you answer.
“Perhaps you are wondering at such a simple code. Yet it serves its purpose; for all messages written with that ink fade completely away a few minutes after they are exposed to the air.”
The men were nearing Broadway. They had reached the fringe of the afternoon crowd. As they turned to cross the street, Clyde Burke was looking straight ahead, toward the surging traffic. Clarendon’s whispering voice was scarcely audible above the din.
“Leave all replies at the Jonas office,” came the final words, “and remember — when you receive a message, read it immediately. For it will fade into nothingness. The words will disappear from your sight, just as I am disappearing—”
It was less than one second before Burke realized that he was no longer listening to the voice of George Clarendon. He turned quickly to look at the man beside him. There was no one there.
Burke glanced up and down the street, peering into the faces of the passers-by. Clarendon was gone.
Yet, while Burke stood alone on the curb, his ears caught the sound of a laugh that he remembered.
Burke looked in vain for the author of the laugh. Then he crossed the street, and mingled, still wondering, with the Broadway throng.
His mysterious companion had vanished like a shadow — yet not even a shadow remained to betray his presence!