After I had traced them out, following Kennedy's instructions,
they showed nothing, except that they were unrelated to the
epidemic at the hall.

Meanwhile, Kennedy was very busy there. He had a microscope and
slides and test-tubes and chemicals for testing things, and I
don't know what all, for there was not time to initiate me into
all the mysteries. He tested the water from the various driven
wells and in the water-tank, and the milk from the cows;--he
tried to find out what food had come in from outside, though
there was practically none, for the hall was self-supporting.
There was no stone he left unturned.

When I rejoined him that night he was clearly perplexed. I don't
think my report decreased his perplexity, either.

"There is only one thing left as far as I have been able to
discover after one day's work," he said, after we had gone over
our activities for the day. "Jim Bisbee never drank the water
from his own wells. He always drank a bottled water shipped down
from a camp of his in New York State, where he had a remarkable
mountain spring. I tested a number of the full bottles at the
hall, but they were perfectly pure. There wasn't a trace of the
bacillus typhosus in any of them. Then it occurred to me that,
after all, that was not the thing to do. I should test the empty
ones. But there weren't any empty ones. They told me they had all
been taken down to the freight station yesterday to be shipped
back to the camp. I hope they haven't gone yet. Let's drive
around and see if they are there."