nes'
face. Colonel Holmes bridled visibly.

"Now look here, Carnes," he began.

"Oh, horse-feathers!" interrupted Carnes. "The M.I.D. is all right in
its place--Good Lord! What's that?"

* * * * *

The train gave a sudden sickening lurch. Colonel Holmes sprawled in an
undignified heap in one corner of the observation platform. Carnes and
Haggerty kept their feet by hanging on to the rails. From the interior
of the car came cries of alarm. The train righted itself for a moment
and then lurched worse than before. There was a scream of brakes as
the engineer strove to halt the forward progress. The train swayed and
lurched like a ship in a storm. Carnes sprang for the telephone
connected with the engine cab and rang excitedly.

"Hello, Bemis," he cried when an answer came: "take off the brakes!
Keep moving at full speed, no matter what happens. What? Use your gun
on him, man! Keep moving even if the train tips over!"

The train swayed and rocked worse than ever as it began to gather
momentum. Carnes looked back along the track and gasped. For three
hundred yards behind them, the track was sinking out of sight. The
train forged ahead, but it was evident that it also was sinking into
the ground. The track behind them suddenly gave. With a roar like a
hundred buildings collapsing, it sank out of sight in a cloud of dust.
The rear car of the train hung partially over the yawning cavern in
the earth for an instant before the laboring engine dragged it to
solid ground. The swaying and lurching grew less. For a mile it
persisted to a slight degree. With a face the color of a sheet, Carnes
made his way into the train. The President met him at the door.

"What's the trouble, Carnes?" he demanded.

"I am not sure, Mr. President. It felt like an earthquake. A great
cavern opened in the earth behind us. Our train was almost trapped in
it."

"An earthquake! We must stop the train at once and take charge of the
situation. An emergency of that sort demands immediate attention."

"I beg you to do nothing of the sort, sir. Your presence would add
little to the rescue work and your life is too precious to risk."

"But my duty to the people--"

"Is to keep yourself alive, sir! Mr. President, this may well be an
attempt on your life. There are persons who would give anything to do
away with you, especially at present. You have not endeared yourself
to a certain class in calling for a conference of