"Uranis?" ventured the other.
The professor nodded, for he regarded it as the greater success of the two. Without it the Scorpion would be useless; with it a dozen Scorpions could be built, once the facilities were provided. Unfortunately the discovery had been effected too late to win the war for the Fatherland. Besides, he had not received the encouragement from the government that he had deserved, and his soul was consequently embittered.
"Come," he said at last, "we must get back to the aerodrome and watch for these half-witted Englishmen. Once there we can afford to laugh at them. They will soon be held in a vice. But I must send a further message to the Scorpion out on the Hamadian plains, hinting how matters stand. After that communications may have to cease for a while. As for these death-hunters, they will find out presently that they are up against something far more terrible than anything which old Jacob Stendahl or the wood-cutter have ever imagined in their wildest fancy. The secret of the Schwarzwald is not for them. I hold the master-key, Fritz, and when I die that master-key will be broken."
And the two men, who had been aware of the presence of the Englishmen ever since they entered the forest, and had watched them accordingly, now moved off in the same direction which the latter had taken half an hour before.
CHAPTER XVIII
"LIVE WIRES"
Matters in the Schwarzwald were now rapidly nearing a climax; the final contest between German brains and English wit could not much longer be delayed. For the moment Keane and Sharpe, unknown to themselves, were enmeshed in the network of a deathly trap. Nothing less than a miracle, or something approaching the same, could now set them free from their perilous position. One thing was certain, and that was that this clever but unscrupulous mathematician and engineer, who was now their declared enemy, would not hesitate to adopt the most extreme measures to get rid of his unwelcome visitors. Unfortunately his power, which almost approached the supernatural, made him a dangerous and a wily foe.
It was now past midnight, but the two Englishmen, who had left the track some time before at a point where its course was suddenly changed, and had continued their journey by the aid of a luminous compass, and the uncertain light of the moon, came at last to another halt.
"Let us stay here a while, Sharpe," his companion had whispered. "I have a strong premonition of some impending danger."
"The deuce you have!" remarked Sharpe, who well knew what this meant in a man like Keane, whose psychic faculties were not to be sneered at.