followed by a heavy fall. I opened the door, and saw Sir John lying
face downwards on the floor. Hastening towards him, I felt for the
first time the deadly effect of the deoxygenized atmosphere, and before
I reached him I fell first on one knee and then headlong. I realized
that my senses were leaving me, and instinctively crawled back to my
own room, where the oppression was at once lifted, and I stood again
upon my feet, gasping. I closed the door of Sir John's room, thinking
it filled with poisonous fumes, as, indeed, it was. I called loudly for
help, but there was no answer. On opening the door to the main office I
met again what I thought was the noxious vapor. Speedily as I closed
the door, I was impressed by the intense silence of the usually busy
office, and saw that some of the clerks were motionless on the floor,
and others sat with their heads on their desks as if asleep. Even at
this awful moment I did not realize that what I saw was common to all
London, and not, as I imagined, a local disaster, caused by the
breaking of some carboys in our cellar. (It was filled with chemicals
of every 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