ade of thin
sheet-iron with a surface coating of tin. The iron has become magnetized
by induction, and the Earth repels the can just as it repels us. It will
follow us to the dead-line, and probably on to Mars, unless the
sheet-iron loses its polarization. If we had cast out a thing of solid
iron, it would rush ahead of us, instead of falling a little behind, as
this does, for it would have no dead weight to carry. But we could not
put such a thing out of the rear end, for no force would make it fall
that way. If we put it out of the forward port-hole, it would beat us in
the race toward Mars."

I remarked to the doctor that the air-pump seemed to be incorrectly
built, for its action was strangely difficult in the reverse manner that
it should have been. The down strokes went by themselves with a quick
snap, but the up strokes were as if against pressure, and the moment the
handle was released it flew down again. He had not tested the pump at
the surface, as it was of a well-known make, but it certainly seemed to
work backwards. Moreover, the more nearly we had a compartment emptied
of air, the more difficult the pumping should become, but here again the
reverse seemed to be the case, for the longer we worked the easier the
up strokes became.

The temperature of the projectile was still fairly comfortable, and the
doctor allowed the condensed air to issue very slowly into the partial
vacuum in his compartment until it produced a barometric pressure of
twenty-seven. Then we pulled back the bulkhead, and when the new
atmosphere had mixed with the old in my compartment, a pressure of
twenty-eight resulted.

"That is about the way the barometer stands during tempests at sea,"
remarked the doctor. I could not notice much difference from the air we
had previously had. Possibly it was fresher and slightly more
exhilarating.

The effort at the pump had made us both hungry again, and I prepared
from meat extracts a warm and rather thick gravy to put over the
asparagus tips. I attempted to pour it, but it was so light that its
sticky consistency prevented it from running. We had a hundred such
examples daily of the changes which lack of weight caused in the
simplest operations. With sandwiches made of biscuits and condensed
meat, we eked out a luncheon. This must have been about noon, for when
it was over I remember noticing that we no longer needed the gas in the
compartment, for there was a gradually increasing mellow ligh