Reddy lowered himself into the passage and cat-footed to the staircase, winding his way upward, every nerve on edge, and he ready for any emergency.

The soldier was not in evidence yet, but Reddy could now trace the chasseur by the marks on the dusty floor of the passage, for it was still light up here, though the sun, it could be seen through the panel opening in the royal bed chamber, was sinking, and evening was near.

With eyes to the floor and crouched like an Indian trailer, the boy noted that the chasseur had gone toward the panel opening into the dining-hall, at least the traces showed that the footmarks reversed themselves, retracing in the same direction. Reddy could distinguish the soldier’s tracks from those which he and his companions had made that morning, because the legging strap under the man’s shoes was clearly outlined in the dust.

Reddy, seeing that the coast was clear, for the time being, scooted back to where Henri and Billy were anxiously waiting and called them by name. Reddy’s knapsack, jacket, and shoes fell about him in the passage, speedily followed by the two boys. Henri stood on the chair and closed the wall section, which settled back without leaving a seam or mark on the wall surface.

“I’ll bet they won’t find that hole unless they batter down the whole wall,” was Henri’s comment.

The boys lost no time in getting upstairs and into the main passage, and there paused to give Henri a moment to figure the next move.

It was suddenly made manifest that at least one way was blocked, for loud voices rang out in the passage in the direction of the dining-hall.

The chasseur had gone for assistance to aid him in solving the puzzle that he had at first wanted to solve by himself.

Billy and Reddy thought that this time sure they were done for, but Henri was still in the reckoning. He was at home, and knew every crook and cranny in the maze of passages.

As the soldiers approached nearer and nearer, arguing in rapid-fire French as they came, Henri wheeled, slammed the bedroom panel into place, and hustling his companions into a run retreated up the passage to the north, stopping an instant to close the plate over the staircase.