to get irritated unless something held up their work.
Dr. Karst was past the age when she would be likely to be concerned
personally about progeny, but the principle applies.
I wandered around, looking at the unlikely apparatus she used to get her
results, fascinated as always by my failure to recognize much that reminded
me of the physics laboratory I had known when I was an undergraduate, and
being careful not to touch anything. Karst started explaining to Manning
what she was doing and why, but I knew that it was useless for me to try to
follow that technical stuff. If Manning wanted notes, he would dictate
them. My attention was caught by a big box-like contraption in one corner
of the room. It had a hopper-like gadget on one side and I could hear a
sound from it like the whirring of a fan with a background of running
water. It intrigued me.
I moved back to the neighborhood of Dr. Karst and the Colonel and heard her
saying, “The problem amounts to this, Colonel: I am getting a much more
highly radio-active end-product than I want, but there is considerable
variation in the half-life of otherwise equivalent samples. That suggests
to me that I am using a mixture of isotopes but I haven’t been able to
prove it. And frankly, I do not know enough about that end of the field to
be sure of sufficient refinement in my methods. I need Dr. Obre’s help on
that.”
I think those were her words, but I may not be doing her justice, not being
a physicist I understood the part about “half-life.” All radioactive
materials keep right on radiating until they turn into something else,
which takes theoretically forever. As a matter of practice their periods,
or “lives,” are described in terms of how long it takes the original
radiation to drop to one-half strength. That time is called a “half-life”
and each radioactive isotope of an element has its own specific
characteristic half-lifetime.
One of the staff—I forget which one—told me once that any form of matter
can be considered as radioactive in some degree; it’s a question of
intensity and period, or half-life.
“I’ll talk to Dr. Ridpath,” Manning answered her, “and see what can be
arranged. In the meantime you might draw up plans for what you want to
re-equip your laboratory.”
“Thank you, Colonel.”
I could see that Manning was about ready to leave, having pacified her; I
was still curious about the big box that gave out the odd noises.
“May I ask what that is, Doctor?”
“Oh, that? That’s an air-conditioner.”
“Odd-looking one. I’ve never seen one like it.”
“It’s not to condition the air of this room. It’s to remove the radioactive
dust before the exhaust air goes outdoors. We wash the dust out of the foul
air.”
“Where does the water go?”
“Down the drain. Out into the bay eventually, I suppose. ‘
I tried to snap my fingers, which was impossible because of the lead
mittens. “That accounts for it, Colonel!”
“Accounts for what?”
“Accounts for those accusing notes we’ve been getting from the Bureau of
Fisheries. This poisonous dust is being carried out into Chesapeake Bay and
is killing the fish.”
Manning turned to Karst. “Do you think that possible, Doctor?”
I could see her brows draw together through the window in her helmet. “I
hadn’t thought about it,” she admitted. “I’d have to do some figuring on
the possible concentrations before I could give you a definite answer. But
it is possible—yes. However,” she added anxiously, “it would be simple
enough to divert this drain to a sink hole of some sort.”
“Hm-m-m—yes.” He did not say anything for some minutes, simply stood there,
looking at the box.
Presently he said, “This dust is pretty lethal?”
“Quite lethal, Colonel.” There was another long silence.
At last I gathered he had made up his mind about something for he said
decisively, “I am going to see to it that you get Obre’s assistance,
Doctor.”
“Oh, good!”
“—but I want you to help me in return. I am very much interested in this
research of yours, but I want it carried on with a little broader scope. I