an we do,
Professor? You're a scientific man; can't you suggest something which
might help?"

"It's a profound mystery to me, M'Allister," I replied, "but we
certainly do not want to remain hung up in space, so I suggest you
should try several different courses. Surely, in some direction we shall
find a way out of this, and get to our destination."

This plan was tried, M'Allister doggedly setting his course first in one
direction, then in another, and trying to put on enough power to force
the vessel along; but time after time we came to a standstill after
moving very slowly for a short distance.

"It looks as though we were to be hung up here indefinitely," said John.
"We do not seem able to get through this mysterious obstacle, whatever
it may be, or whatever course we may try."

"Oh, we've not tried all points yet," I said. "We must not give up now
we have got so close to the object of our trip. Take a fresh course,
M'Allister."

He took a fresh course, and another after that, but with exactly the
same result.

I had never seen M'Allister in such a perturbed state before; he
actually trembled all over with the intensity of his feelings, and his
face had an expression of grim determination such as I should imagine
might be seen on the face of a soldier at bay with his back to a wall,
and fighting for his life against overwhelming numbers of assailants.

"My word!" he exclaimed, "yon's Mars, and here's us, but it doesn't seem
as if we should ever come together. Losh mon, bonnie Scotland for ever!
Here goes for another try!" and he switched on the current again with a
vicious pull.

We watched the machines with intense anxiety, wondering whether this new
course would be any better than the others we had tried--whether the
machines would keep moving, or slow down and stop as before.

No, we kept moving; and soon it was evident we were gaining speed
rapidly.

"Hurrah, hurrah!" I cried in exultation. "We are doing it this time.
Slow down, M'Allister, we are going too fast now!"

"Scotland for ever!" he shrieked. "That did it, Professor!"

Strangely enough, John, usually the most excitable member of our party,
was the calmest of the three, and simply remarked quietly, "We've done
it this time."

Yes, we had indeed done it this time, but our attention had been so
taken up with our anxious watching of the machines that none of us had
noticed the direction we were taking.

We had passed entirely through the