been forwarded from my lodgings
at Streatham. The message was from the very man we had been discussing,
and ran thus:--

Malone, 17, Hill Street, Streatham.--Bring oxygen.--Challenger.

"Bring oxygen!" The Professor, as I remembered him, had an elephantine
sense of humour capable of the most clumsy and unwieldly gambollings.
Was this one of those jokes which used to reduce him to uproarious
laughter, when his eyes would disappear and he was all gaping mouth and
wagging beard, supremely indifferent to the gravity of all around him? I
turned the words over, but could make nothing even remotely jocose out of
them. Then surely it was a concise order--though a very strange one. He
was the last man in the world whose deliberate command I should care to
disobey. Possibly some chemical experiment was afoot; possibly----Well,
it was no business of mine to speculate upon why he wanted it. I must
get it. There was nearly an hour before I should catch the train at
Victoria. I took a taxi, and having ascertained the address from the
telephone book, I made for the Oxygen Tube Supply Company in Oxford
Street.

As I alighted on the pavement at my destination, two youths emerged from
the door of the establishment carrying an iron cylinder, which, with some
trouble, they hoisted into a waiting motor-car. An elderly man was at
their heels scolding and directing in a creaky, sardonic voice. He
turned towards me. There was no mistaking those austere features and
that goatee beard. It was my old cross-grained companion, Professor
Summerlee.

"What!" he cried. "Don't tell me that _you_ have had one of these
preposterous telegrams for oxygen?"

I exhibited it.

"Well, well! I have had one too, and, as you see, very much against the
grain, I have acted upon it. Our good friend is as impossible as ever.
The need for oxygen could not have been so urgent that he must desert the
usual means of supply and encroach upon the time of those who are really
busier than himself. Why could he not order it direct?"

I could only suggest that he probably wanted it at once.

"Or thought he did, which is quite another matter. But it is superfluous
now for you to purchase any, since I have this considerable supply."

"Still, for some reason he seems to wish that I should bring oxygen too.
It will be safer to do exactly what he tells me."

Accordingly, in spite of many grumbles and remonstrances from Summerlee,
I ordered an addition