But Maget thought of Juan, and then he knew he did not want Durkin, in
spite of his failings, to perish so. He ran for the door, and across
the clearing.

"Durkin--Bill--wait, it's Frank--"

Great bellowings sounded from the bowels of the earth, but Maget
ignored these in his effort to save his partner. Durkin had the
padlock off the stone shack, and pulled back the door.

As the door disclosed the interior, Maget could see that a greenish
haze filled the entire building. Wan liquid light streamed forth like
heavy fluid.

Bravely, to save his pal from death, Maget ran forward. But Durkin had
entered the stone shack.

Maget went to the very door of the building. Durkin was inside, and
Maget could see his partner's thick form as a black object in the
strange, thick air.

An eery scream came suddenly from Durkin's lips; Maget wrung his hands
and called for help.

"Come out, Bill, come out," he cried.

Durkin evidently tried to obey, for he turned toward the door. But his
knees seemed to give way beneath him, he threw his arm across his eyes
as he sank to the ground, crying in agony, incoherent sounds issuing
from his lips.

Shriek after shriek the unfortunate man uttered. As Maget made a dash
forward to take a chance with death and rescue his friend, Professor
Gurlone and his son Kenneth ran up and threw a black cloak over the
tramp.

The three entered the shack of death. Maget, not entirely covered,
felt his heart give a terrific jump, and he gasped for breath. Durkin
was quivering on the floor which was lined with lead.

* * * * *

Round vials stood about the room like a battery of search-lights, and
from these emanated the deadly green haze.

But almost before Maget touched his pal, Durkin was dead. Curled up as
though sewed together by heavy cords. Durkin lay in a ball, a shaking
mass of burned flesh.

The two Gurlones pushed out ahead of them, and raised their hands.
They had on their black suits and their helmets.

"It is too late to do anything for him now," said Kenneth Gurlone
sadly. "He was headstrong. You can see for yourself that the five
million dollars takes care of itself. Certain death goes with it if
you are unprotected. These lead-cloth suits will keep off the rays for
a short time. We always wear them when we are working with the metal,
even when we have a lead screen."

"Poor Bill," sobbed Maget. "It's terrible!"

Professor Gurlone shrugged. "It w