poned. I'll move as swiftly as I can and I ought to be at Fallon
to-night if I'm lucky and don't run into any obstacles. Burros are
fairly slow, but I'll make the best time possible."

"I rather expected you would, Doctor. I can't get my pack train together
until evening, so I'll wait for you right here. I'm mighty glad that you
are going to get in on it."

* * * * *

Silently Carnes and Dr. Bird surveyed the wreck of the T. A. C. plane.
The observations of the secret service operative had been correct. The
bodies of the unfortunate crew had been broken into fragments. Their
limbs had not been twisted off as a freak of the fall but had been
cleanly broken off, as though the bodies had suddenly become brittle and
had shattered on their impact with the ground. Not only the bodies, but
the ship itself had been broken up. Even the clothing of the men was in
pieces or had long splits in the fabric whose edges were as clean as
though they had been cut with a knife.

Dr. Bird picked up an arm which had belonged to the pilot and examined
it. The brittleness, if it had ever existed, was gone and the arm was
limp.

"No _rigor mortis_," commented the Doctor. "How long ago was the
wreck?"

"About seventy-two hours ago."

"Hm-m! What about those packets that were on the plane?"

Carnes stepped forward and gingerly inspected first the body of the army
courier and then that of the courier of the T. A. C.

"Both gone, Doctor," he reported, straightening up.

Dr. Bird's face fell into grim lines.

"There is more to this case than appears on the surface, Carnes," he
said. "This was no ordinary wreck. Bring up that third burro; I want to
examine these fragments a little. Bill," he went on to one of the two
guides who had accompanied them from Fallon, "you and Walter scout
around the ground and see what you can find out. I especially wish to
know whether anyone has visited the scene of the wreck."

* * * * *

The guides consulted a moment and started out. Carnes drove up the burro
the Doctor had indicated and Dr. Bird unpacked it. He opened a mahogony
case and took from it a high powered microscope. Setting the instrument
up on a convenient rock, he subjected portions of the wreck, including
several fragments of flesh, to a careful scrutiny. When he had completed
his observations he fell into a brown study, from which he was aroused
by Carnes.

"What did you fi