ime for the metal to cool. Everything else had been
done or made ready. The huge projectile which was to wing its way into
Space to do battle for the life of humanity was completed. The boring
and rifling tools were finished, and all the materials for the driving
and the bursting charges were ready at hand for putting into their final
form when the work of loading up began. There was literally nothing more
to be done. All that human labour, skill and foresight could achieve for
the present had been accomplished.

Dearly would he have loved to go south and join the ranks of the
fighters; but a higher sense of duty than personal courage forbade that.
He was the only man who could perform the task he had undertaken, and a
chance bullet fragment of a shell to say nothing of the hundred minor
chances of the battlefield, might make the doing of that work
impossible.

No, his time would come in the awful moment when the fate of humanity
would hang in the balance, and his place alike of honour and of duty
was now in the equatorial room of the observatory at Whernside, watching
through every waking hour of his life the movements of the Invader, that
he might note the slightest deviation from its course, or the most
trifling change in its velocity. For on such seemingly small matters as
these depended, not only the fate of the world, but of the only woman
who could make the world at least worth living in for him--and so he
went to Whernside by the morning train after a long day's talk with Tom
Bowcock over things in general.

"Yo' may be sure that everything will be all right, Mr Lennard," said
Tom, as they shook hands on the platform. "I'll take t' temperatures,
top, bottom and middle, every night and morning and post them to yo',
and if there's any change that we don't expect, I'll wire yo' at once;
and now I've a great favour to ask you, Mr Lennard. I haven't asked it
before because there's been too much work to do--"

"You needn't ask it, Tom," laughed Lennard, as he returned his grip,
"but I'm not going to invite you to Whernside just yet, for two reasons.
In the first place, I can't trust that metal to anyone else but you for
at least a week; and in the second place, when I do send you an
invitation from Mr Parmenter I shall not only be able to show you the
comet a bit brighter than it is just now, but something else that you
may have thought about or read about but never seen yet, and I am going
to give you an experien