r at once," declared Hart, returning from the
telephone. "Simler and his staff are there and we are wanted
immediately."

"Oh, Jack!" Marie begged with her eyes.

"Got to be done, Honey," I responded, "and, believe me, I am going to do
what little I can to help. Suppose we surrendered!"

* * * * *

I shuddered anew at the very thought and took hurried leave of my
family, Hart and George awaiting me in the hall. Had I known what was to
transpire before the end of the war, I am certain I would have been in
much less of a hurry.

We rushed to the hangar, where Secretary Simler and his party awaited us
in the office. Rather, I should say, they waited for Hart Jones.

"Mr. Jones," said the Secretary of War, when the introductions were
over, "it is up to you to get the _Pioneer_ in shape to go out after
these terrible creatures before the forty-eight hours have expired. We
have replied to their ultimatum and have told them we will have our
answer ready within the appointed time, but it is already agreed between
the nations of the World Alliance that our reply is to be negative.
Better far that we submit to the utter destruction of our civilization
than agree to their terms."

"I believe I can do it, Mr. Secretary," was Hart Jones' simple comment.
"At least I will try. But you must let me have an experienced astronomer
at once with whom to consult."

"Astronomer?"

"Yes--immediately. I have a theory, but am not enough of a student of
astronomy myself to work it out."

"You shall have the best man in the Air Naval Observatory at once."
Secretary Simler chewed his cigar savagely. "And anything else you might
need," he concluded.

"There is nothing else, sir." Hart turned from the great men who
regarded him solemnly, some with expressions of hope, others with plain
distrust written large on their countenances.

* * * * *

They left in silence and we returned to our work with renewed vigor.
Within an hour there arrived by fast plane an undersized,
thick-spectacled man can who presented himself as Professor Linquist
from the government observatory. He was immediately taken into the
office by Hart and the two remained behind closed doors for the best
part of four hours.

Meanwhile the hangar hummed with activity as usual. We in the chemical
laboratory were engaged in compounding the high explosive used as fuel
in the _Pioneer_. This was being compressed