"How do you account for it?" asked Gridley.
"I can't account for it," replied Von Horst. "It is as though we were moving along in the center of a procession with all the savage carnivores behind us."
"This perpetual noonday sun has its compensations," remarked Gridley with a laugh, "for at least it insures that we shall not have to spend the night here."
At that instant the attention of the two men was attracted by an exclamation from one of the Waziri behind them. "Look, Bwana! Look!" cried the man, pointing back along the trail. Following the direction of the Waziri's extended finger, Gridley and Von Horst saw a huge beast slinking slowly along the trail in their rear.
"God!" exclaimed Von Horst, "and I thought Dorf was exaggerating."
"It doesn't seem possible," exclaimed Gridley, "that five hundred miles below our feet automobiles are dashing through crowded streets lined by enormous buildings; that there the telegraph, the telephone and the radio are so commonplace as to excite no comment; that countless thousands live out their entire lives without ever having to use a weapon in self-defense, and yet at the same instant we stand here facing a saber-tooth tiger in surroundings that may not have existed upon the outer crust for a million years."
"Look at them!" exclaimed Von Horst. "If there is one there are a dozen of them."
"Shall we fire, Bwana?" asked one of the Waziri.
"Not yet," said Gridley. "Close up and be ready. They seem to be only following us."
Slowly the party fell back, a line of Waziri in the rear facing the tigers and backing slowly away from them. Muviro dropped back to Gridley's side.