tried to reach the rapidly passing vehicle, but had been too late.

That was all that anyone knew, nor did Lady Greystoke dream of the possible identity of the man at the bottom of the plot until her husband told her of the escape of Nikolas Rokoff from the French prison where they had hoped he was permanently confined.

As Tarzan and his wife stood planning the wisest course to pursue, the telephone bell rang in the library at their right. Tarzan quickly answered the call in person.

"Lord Greystoke?" asked a man's voice at the other end of the line.

"Yes."

"Your son has been stolen," continued the voice, "and I alone may help you to recover him. I am conversant with the plot of those who took him. In fact, I was a party to it, and was to share in the reward, but now they are trying to ditch me, and to be quits with them I will aid you to recover him on condition that you will not prosecute me for my part in the crime. What do you say?"

"If you lead me to where my son is hidden," replied the ape-man, "you need fear nothing from me."

"Good," replied the other. "But you must come alone to meet me, for it is enough that I must trust you. I cannot take the chance of permitting others to learn my identity."

"Where and when may I meet you?" asked Tarzan.

The other gave the name and location of a public-house on the water-front at Dover--a place frequented by sailors.

"Come," he concluded, "about ten o'clock tonight. It would do no good to arrive earlier. Your son will be safe enough in the meantime, and I can then lead you secretly to where he is hidden. But be sure to come alone, and under no circumstances notify Scotland Yard, for I know you well and shall be watching for you.

"Should any other accompany you, or should I see suspicious characters who might be agents of the police, I shall not meet you, and your last chance of recovering your son will be gone."

Without more words the man rang off.

Tarzan repeated the gist of the conversation to his wife. She begged to be allowed to accompany him, but he insisted that it might result in the man's carrying out his threat of refusing to aid them if Tarzan did not come alone, and so they parted, he to hasten to Dover, and she, ostensibly to wait at home until he should notify her of the outcome of his mission.

Little did either dream of what both were destined to pass through before they should meet again, or the far-distant--but why anticipate?

For ten minutes after the ape-man had left her Jane Clayton walked restlessly back and forth across the silken rugs of the library. Her mother heart ached, bereft of its firstborn. Her mind was in an anguish of hopes and fears.

Though her judgment told her that all would be well were her Tarzan to go alone in accordance with the mysterious stranger's summons, her intuition would not permit her to lay aside suspicion of the gravest dangers to both her husband and her son.

The more she thought of the matter, the more convinced she became that the recent telephone message might be but a ruse to keep them inactive until the boy was safely hidden away or spirited out of England. Or it might be that it had been simply a bait to lure Tarzan into the hands of the implacable Rokoff.

With the lodgment of this thought she stopped in wide-eyed terror. Instantly it became a conviction. She glanced at the great clock ticking the minutes in the corner of the library.

It was too late to catch the Dover train that Tarzan was to take. There was another, later, however, that would bring her to the Channel port in time to reach the address the stranger had given her husband before the appointed hour.

Summoning her maid and chauffeur, she issued instructions rapidly. Ten minutes later she was being whisked through the crowded streets toward the railway station.

It was nine-forty-five that night that Tarzan entered the squalid