ry kind, of whose properties I was ignorant, dealing as I did
with the accountant, and not the scientific side of our business.) I
opened the only window in my room, and again shouted for help. The
street was silent and dark in the ominously still fog, and what now
froze me with horror was meeting the same deadly, stifling atmosphere
that was in the rooms. In falling I brought down the window, and shut
out the poisonous air. Again I revived, and slowly the true state of
things began to dawn upon me.

I was in an oasis of oxygen. I at once surmised that the machine on my
shelf was responsible for the existence of this oasis in a vast desert
of deadly gas. I took down the American's machine, fearful in moving it
that I might stop its working. Taking the mouthpiece between my lips I
again entered Sir John's room, this time without feeling any ill
effects. My poor master was long beyond human help. There was evidently
no one alive in the building except myself. Out in the street all was
silent and dark. The gas was extinguished, but here and there in shops
the incandescent lights were still weirdly burning, depending, as they
did, on accumulators, and not on direct engine power. I turned
automatically towards Cannon Street Station, knowing my way to it even
if blindfolded, stumbling over bodies prone on the pavement, and in
crossing the street I ran against a motionless 'bus, spectral in the
fog, with dead horses lying in front, and their reins dangling from the
nerveless hand of a dead driver. The ghostlike passengers, equally
silent, sat bolt upright, or hung over the edge boards in attitudes
horribly grotesque.

VII.--THE TRAIN WITH ITS TRAIL OF THE DEAD.

If a man's reasoning faculties were alert at such a time (I confess
mine were dormant), he would have known there could be no trains at
Cannon Street Station, for if there was not enough oxygen in the air to
keep a man alive, or a gas-jet alight, there would certainly not be
enough to enable an engine fire to burn, even if the engineer retained
sufficient energy to attend to his task. At times instinct is better
than reason, and it proved so in this case. The railway from Ealing in
those days came under the City in a deep tunnel. It would appear that
in this underground passage the carbonic acid gas would first find a
resting-place on account of its weight; but such was not the fact. I
imagine that a current through the tunnel brought from the outlying
distr