s condition was more serious. Not only was the old man's
frail strength nearly exhausted, but he was also badly wounded. His
thin chest was seared by two great livid areas of burned flesh, the
nature of which puzzled Dixon as he began to dress the injuries. They
seemed of radioactive origin, yet in many ways they were unlike any
radium burns that Dixon had ever seen.

While Dixon was working over him, Crawford stirred weakly and opened
his eyes. He sighed in relief as he recognized his surroundings.

"Good boy, Bruce!" he commended wanly. "We are safe here among the
insulating veins of lead ore in the mountain. This is where Ruth and I
were trying to come after we escaped from those devils to-night. But,
Bruce, how did you guess the radioactive nature of the Green Sickness
in time to avoid falling a victim to it as soon as you left the
shelter of your laboratory?"

"My escape was entirely luck," Dixon admitted grimly. "To-night I left
my laboratory for the first time in three days. I found a world gone
mad, with a strange green moon blazing down upon a land of living dead
men, and with marauding monsters hideous enough to have been spawned
in the Pit itself. What in Heaven's name does it all mean?"

* * * * *

"I am afraid that it means the end of the world, Bruce," Crawford
answered quietly. "It was a little over forty-eight hours ago that the
incredible event first happened. Without a moment's warning, _the moon
turned green_! Hardly had the world's astronomers had time to
speculate upon this amazing phenomenon before the Green Sickness
struck--a pestilence of appalling deadliness that swept resistlessly
in the path of those weird green rays. Wherever the green moon shone,
every living creature succumbed with ghastly swiftness to the
condition of living death that you have seen.

"Westward with the racing moon sped the Green Sickness, and nothing
stayed its attack. The green rays pierced through buildings of wood,
stone, and iron as though they did not exist. A doomed world had
neither time nor opportunity to guess that lead was the one armor
against those dread rays. To-night, Bruce, we are in all probability
the only three human beings on this planet who are not slumbering in
the paralytic stupor of the Green Sickness.

"Ruth and I were stricken with the rest of the world," Crawford
continued. "We recovered consciousness hours later to find ourselves
captives in the Earth-camp