ce, into your blood while you slept, thereby
baffling some of the functions of your extraordinary brain. The night
when in your sleep you stirred once, and had you stirred twice, I would
have killed you, then and there, as ruthlessly as you would kill mankind
now. The night I did kill your lieutenant, Rockingham, and throw his
body overboard to the sharks."

Brande did not speak for a moment. Then he said in a gentle,
uncomplaining voice:

"So it now devolves on Grey. The end will be the same. The Labrador
expedition will succeed where I have failed." To Natalie: "You had
better go. There will only be an explosion. The island will probably
disappear. That will be all."

"Do you remain?" she asked.

"Yes. I perish with my failure."

"Then I perish with you. And you, Marcel, save yourself--you coward!"

I started as if struck in the face. Then I said to Edith: "Be careful to
keep to the track. Take the bay horse. I saddled him for myself, but you
can ride him safely. Lose no time, and ride hard for the coast."

"Arthur Marcel," she answered, so softly that the others did not hear,
"your work in the world is not yet over. There is the Labrador
expedition. Just now, when my strength failed, you whispered 'courage.'
Be true to yourself! Half an hour is gone."

At length some glimmer of human feeling awoke in Brande. He said in a
low, abstracted voice: "My life fittingly ends now. To keep you,
Natalie, would only be a vulgar murder." The old will power seemed to
come back to him. He looked into the girl's eyes, and said slowly and
sternly: "Go! I command it."

Without another word he turned away from us. When he had disappeared
into the laboratory, Natalie sighed, and said dreamily:

"I am ready. Let us go."

CHAPTER XVIII.

THE FLIGHT.

I led the girls hurriedly to the horses. When they were mounted on the
ponies, I gave the bridle-reins of the bay horse--whose size and
strength were necessary for my extra weight--to Edith Metford, and asked
her to wait for me until I announced Brande's probable failure to the
people, and advised a _sauve qui peut_.

Hard upon my warning there followed a strange metamorphosis in the
crowd, who, after the passing weakness at the lecture, had fallen back
into stoical indifference, or it may have been despair. The possibility
of escape galvanized them into the desire for life. Cries of distress,
and prayers for help, filled the air. Men and women rushed about like
fri