Tarzan and Mpingu had proceeded but a short distance down the avenue when the black motioned the ape-man to the side of the street, where a small gate was let into a solid wall. "We are here," said Mpingu. "This is not the home of Dion Splendidus," said Tarzan, immediately suspicious. Mpingu was surprised that this stranger should so well remember the location of a house that he had visited but once, and that more than three weeks since, but he did not know the training that had been the ape-man's through the long years of moving through the trackless jungle that had trained his every sense and faculty to the finest point of orientation. "It is not the main gate," replied Mpingu, quickly, "but Maximus Praeclarus did not think it safe that you be seen entering the main gate of the home of Dion Splendidus in the event that, by any chance, you were observed. This way leads into a lane that might connect with any one of several homes, and once in it there is little or no chance of apprehension." "I see," said Tarzan. "Lead the way." Mpingu opened the gate and motioned Tarzan in ahead of him, and as the ape-man passed through into the blackness beyond there fell upon him what seemed to be a score of men and he was borne down in the same instant that he realized that he had been betrayed. So rapidly did his assailants work that it was a matter of seconds only before the ape-man found shackles upon his wrists, the one thing that he feared and hated most. _Chapter Thirteen_ While Erich von Harben wooed Favonia beneath a summer moon in the garden of Septimus Favonius in the island city of Castrum Mare, a detachment of the brown legionaries of Sublatus Imperator dragged Tarzan of the Apes and Mpingu, the black slave of Dion Splendidus, to the dungeons beneath the Colosseum of Castra Sanguinarius--and far to the south a little monkey shivered from cold and terror in the topmost branches of a jungle giant, while Sheeta the panther crept softly through the black shadows far below. In the banquet hall of his host, Maximus Praeclarus reclined upon a sofa far down the board from Fastus, the guest of honor. The prince, his tongue loosed by frequent drafts of native wine, seemed in unusually good spirits, radiating self-satisfaction. Several times he had brought the subject of conversation around to the strange white barbarian, who had insulted his sire and twice escaped from the soldiers of Sublatus. "He would never have escaped from me that day," he boasted, throwing a sneer in the direction of Maximus Praeclarus, "nor from any other officer who is loyal to Caesar." "You had him, Fastus, in the garden of Dion Splendidus," retorted Praeclarus. "Why did you not hold him?" Fastus flushed. "I shall hold him this time," he blurted.