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 onehalf 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 reequip 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 a.s.sistance, 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 want you to investigate for maxima both in period and intensity as well as for minima. I want you to drop the strictly utilitarian approach and make an exhaustive research along lines which we will work out in greater detail later."

She started to say something but he cut in ahead of her. "A really thorough program of research should prove more helpful in the long run to your original purpose than a more narrow one. And I shall make it my business to expedite every possible facility for such a research. I think we may turn up a number of interesting things."

He left immediately, giving her no time to discuss it. He did not seem to want to talk on the way back and I held my peace. I think he had already gotten a glimmering of the bold and drastic strategy this was to lead to, but even Manning could not have thought out that early the inescapable consequences of a few dead fish-otherwise he would never have ordered the research.

No, I don't really believe that. He would have gone right ahead, knowing that if he did not do it, someone else would. He would have accepted the responsibility while bitterly aware of its weight.

1944 wore along with no great excitement on the surface. Karst got her new laboratory equipment and so much additional help that her department rapidly became the largest on the grounds. The explosives research was suspended after a conference between Manning and Ridpath, of which I heard only the end, but the meat of it was that there existed not even a remote possibility at that time of utilizing U235 as an explosive. As a source of power, yes, sometime in the distant future when there had been more opportunity to deal with the extremely ticklish problem of controlling the nuclear reaction. Even then it seemed likely that it would riot be a source of power in prime movers such as rocket motors or mobiles, but would be used in vast power plants at least as large as the Boulder Dam installation.

After that Ridpath became a sort of co-chairman of Karst's department and the equipment formerly used by the explosives department was adapted or replaced to carry on research on the deadly artificial radioactives. Manning arranged a division of labor and Karst stuck to her original problem of developing techniques for tailor-making radioactives. I think she was perfectly happy, sticking with a one-track mind to the problem at hand. I don't know to this day whether or not Manning and Ridpath ever saw fit to discuss with her what they intended to do.

As a matter of fact, I was too busy myself to think much about it. The general elections were coming up and I was determined that Manning should have a const.i.tuency to return to, when the emergency was over. He was not much interested,'but agreed to let his name be filed as a candidate for re-election. I was trying to work up a campaign by remote control and cursing because I could not be in the field to deal with the thousand and one emergencies as they arose.

I did the next best thing and had a private line installed to permit the campaign chairman to reach me easily. I don't think I violated the Hatch Act, but I guess I stretched it a little. Anyhow, it turned out all right; Manning was elected as were several other members of the citizen-military that year. An attempt was made to smear him by claiming that he was taking two salaries for one job, but we squelched that with a pamphlet ent.i.tled "For Shame!" which explained that he got one salary for two jobs. That's the Federal law in such cases and people are ent.i.tled to know it.

It was just before Christmas that Manning first admitted to me how much the implications of the KarstObre process were preying on his mind. He called me into his office over some inconsequential matter, then did not let me go. I saw that he wanted to taik.

"How much of the K-O dust do we now have on hand?" he asked suddenly.

"Just short of ten thousand units," I replied. "I can look up the exact figures in half a moment." A unit would take care of a thousand men, at normal dispersion. He knew the figure as well as I did, and I knew he was stalling.

We had shifted almost imperceptibly from research to manufacture, entirely on Manning's initiative and authority. Manning had never made a specific report to the Department about it, unless he had done so orally to the Chief of Staff.

"Never mind," he answered to my suggestion, then added, "Did you see those horses?"

"Yes," I said briefly.

I did not want to talk about it. I like horses. We hac requisitioned six broken-down old nags, ready for th bone yard, and had used them experimentally. W knew now what the dust would do. After they had died any part of their carca.s.ses would register on a photo graphic plate and tissue from the apices of their lung1 and from the bronchia glowed with a light of its own. Manning stood at the window, staring out at th dreary Maryland winter for a minute or two before re plying, "John, I wish that radioactivity had never beer discovered. Do you realize what that devilish stuf amounts to?"

"Well," I said, "it's a weapon, about like poisor gas-maybe more efficient."

"Rats!" he said, and for a moment I thought he wa~ annoyed with me personally. "That's about like corn paring a sixteen-inch gun with a bow and arrow We've got here the first weapon the world has eve~ seen against which there is no defense, none whatso ever. It's death itself, C.O.D.

"Have you seen Ridpath's report?" he went on. I had not. Ridpath had taken to delivering his re ports by hand to Manning personally.

"Well," he said, "ever since we started productioi I've had all the talent we could spare working on th problem of a defense against the dust. Ridpath telL me and I agree with him that there is no means what soever to combat the stuff, once it's used."

"How about armor," I asked, "and protective cloth ing?"

"Sure, sure," he agreed irritatedly, "provided yoi never take it off to eat, or to drink or for any purpos whatever, until the radioaction has ceased, or you ar out of the danger zone. That is all right for laborator work; I'm talking about war."

I considered the matter. "I still don't see what yoi are fretting about, Colonel. If the stuff is as good as yo~ say it is, you've done just exactly what you set out t odo-develop a weapon which would give the United States protection against aggression."

He swung around. "John, there are times when I think you are downright stupid!"

I said nothing. I knew him and I knew how to discount his moods. The fact that he permitted me to see his feelings is the finest compliment I have ever had. "Look at it this way," he went on more patiently; "this dust, as a weapon, is not just simply sufficient to safeguard the United States, it amounts to a loaded gun held at the head of every man, woman, and child on the globe!"

"Well," I answered, "what of that? It's our secret, and we've got the upper hand. The United States can put a stop to this war, and any other war. We can declare a Pax Americana, and enforce it."

"Hm-m-m-I wish it were that easy. But it won't remain our secret; you can count on that. It doesn't matter how successfully we guard it; all that anyone needs is the hint given by the dust itself and then it is just a matter of time until some other nation develops a technique to produce it. You can't stop brains from working, John; the reinvention of the method is a mathematical certainty, once they know what it is they are looking for. And uranium is a common enough substance, widely distributed over the globe-don't forget that!

"It's like this: Once the secret is out-and it will be out if we ever use the stuff!-the whole world will be comparable to a room full of men, each armed with a loaded .45. They can't get out of the room and each one is dependent on the good will of every other one to stay alive. All offense and no defense. See what I mean?"

I thought about it, but I still didn't guess at the difficulties. It seemed to me that a peace enforced by us was the only way out, with precautions taken to see that we controlled the sources of uranium. I had the usual American subconscious conviction that our country would never use power in sheer aggressior Later, I thought about the Mexican War and the Spar ish-American War and some of the things we did i Central America, and I was not so sure- It was a couple of weeks later, shortly after inauguration day, that Manning told me to get the Chief of Staff's office on the telephone. I heard only the tail en of the conversation. "No, General, I won't," Manning was saying. "I won't discuss it with you, or the Secr tary, either. This is a matter the Commander in Chi is going to have to decide in the long run. If he turns down, it is imperative that no one else ever knoi~ about it. That's my considered opinion.. . . What that? . . . I took this job under the condition that I wa to have a free hand. You've got to give me a little le way this time.. . . Don't go bra.s.s hat on me. I kne~ you when you were a plebe... . O.K., O.K., sorry... If the Secretary of War won't listen to reason, you te him I'll be in my seat in the House of Representativc tomorrow, and that I'll get the favor I want from th majority leader. . . . All right. Good-bye."

Washington rang up again about an hour later.] was the Secretary of War. This time Manning listene more than he talked. Toward the end, he said, "All want is thirty minutes alone with the President. I nothing comes of it, no harm has been done. If I convince him, then you will know all about it. . . . No, Sir."

I did not mean that you would avoid responsibility. intended to be helpful. . . . Fine! Thank you, Mr. Se retary."

The White House rang up later in the day and set time.

We drove down to the District the next day throug a nasty cold rain that threatened to turn to sleet.

TF usual congestion in Washington was made worse b the weather; it very nearly caused us to be late in a: riving. I could hear Manning swearing under his breath all the way down Rhode Island Avenue. But we were dropped at the west wing entrance to the White House with two minutes to spare. Manning was ushered into the Oval Office almost at once and I was left cooling my heels and trying to get comfortable in civilian clothes. After so many months of uniform they itched in the wrong places.

The thirty minutes went by.

The President's reception secretary went in, and came out very promptly indeed. He stepped on out into the outer reception room and I heard something that began with, "I'm sorry, Senator, but-" He came back in, made a penciled notation, and pa.s.sed it out to an usher.

Two more hours went by.

Manning appeared at the door at last and the secretary looked relieved. But he did not come out, saying instead, "Come in, John. The President wants to take a look at you."

I fell over my feet getting up.

Manning said, "Mr. President, this is Captain DeFries." The President nodded, and I bowed, unable to say anything. He was standing on the hearth rug, his fine head turned toward us, and looking just like his pictures-but it seemed strange for the President of the United States not to be a tall man.

I had never seen him before, though, of course, I knew something of his record the two years he had been in the Senate and while he was Mayor before that.

The President said, "Sit down, DeFries. Care to smoke?" Then to Manning. "You think he can do it?"

"I think he'll have to. It's Hobson's choice."

"And you are sure of him?"

"He was my campaign manager."

"I see."

The President said nothing more for a while and G.o.d knows I didn't!-though I was bursting to know what they were talking about. He commenced again with, "Colonel Manning, I intend to follow the procedur you have suggested, with the changes we discusse But I will be down tomorrow to see for myself that th dust will do what you say it will. Can you prepare demonstration?"

"Yes, Mr. President."

"Very well, we will use Captain DeFries unless think of a better procedure." I thought for a momer that they planned to use me for a guinea pig! But h turned to me and continued, "Captain, I expect to sen you to England as my representative."

I gulped. "Yes, Mr. President." And that is ever word I had to say in calling on the President of th United States.

After that, Manning had to tell me a lot of things h had on his mind. I am going to try to relate them ~ carefully as possible, even at the risk of being dull an obvious and of repeating things that are commo knowledge.

We had a weapon that could not be stopped. An type of K-O dust scattered over an area rendered th~ area uninhabitable for a length of time that depende on the half-life of the radioactivity.

Period. Full stop.

Once an area was dusted there was nothing th~ could be done about it until the radioactivity ha fallen off to the point where it was no longer harmfu The dust could not be cleaned out; it was everywhen There was no possible way to counteract it-burn i combine it chemically; the radioactive isotope w~ still there, still radioactive, still deadly. Once used o a stretch of land, for a predetermined length of tim that piece of earth would not tolerate life.

It was extremely simple to use. No complicate bomb-~ights were needed, no care need be taken to h "military objectives." Take it aloft in any sort of aircraft, attain a position more or less over the area yo wish to sterilize, and drop the stuff. Those on the ground in the contaminated area are dead men, dead in an hour, a day, a week, a month, depending on the degree of the infection-but dead.

Manning told me that he had once seriously considered, in the middle of the night, recommending that every single person, including himself, who knew the Karst-Obre technique be put to death, in the interests of all civilization. But he had realized the next day that it had been sheer funk; the technique was certain in time to be rediscovered by someone else.

Furthermore, it would not do to wait, to refrain from using the grisly power, until someone else perfected it and used it. The only possible chance to keep the world from being turned into one huge morgue was for us to use the power first and drastically-get the upper hand and keep it.

We were not at war, legally, yet we had been in the war up to our necks with our weight on the side of democracy since 1940. Manning had proposed to the President that we turn a supply of the dust over to Great Britain, under conditions we specified, and enable them thereby to force a peace. But the terms of the peace would be dictated by the United States-for we were not turning over the secret.

After that, the Pax Americana.

The United States was having power thrust on it, w.i.l.l.y-nilly. We had to accept it and enforce a worldwide peace, ruthlessly and drastically, or it would be seized by some other nation. There could not be coequals in the possession of this weapon. The factor of time predominated.

I was selected to handle the details in England because Manning insisted, and the President agreed with him, that every person technically acquainted with the Karst-Obre process should remain on the laboratory reservation in what amounted to protective custody-imprisonment. That included Manning himself.

I could go because I did not have the secret-I coul not even have acquired it without years of schoolingand what I did not know I could not tell, even under well, drugs. We were determined to keep the secret a long as we could to consolidate the Pax; we did nc distrust our English cousins, but they were Britisher with a first loyalty to the British Empire. No need to tempt them.

I was picked because I understood the backgroun if not the science, and because Manning trusted me. don't know why the President trusted me, too, hi. then my job was not complicated.

We took off from the new field outside Baltimore o a cold, raw afternoon which matched my own feeling I had an all-gone feeling in my stomach, a runny nos and, b.u.t.toned inside my clothes, papers appointin me a special agent of the President of the Unite States. They were odd papers, papers without prec~ dent; they did not simply give me the usual diplomati immunity; they made my person very nearly as sacre as that of the President himself.

At Nova Scotia we touched ground to refuel, tF F.B.I. men left us, we took off again, and the Canadia transfighters took their stations around us. All the du: we were sending was in my plane; if the President representative were shot down, the dust would go 1 the bottom with him.

No need to tell of the crossing. I was airsick and mi erable, in spite of the steadiness of the new six-engine jobs. I felt like a hangman on the way to an executio] and wished to G.o.d that I were a boy again, with not] ing more momentous than a debate contest, or a trac meet, to worry me.

There was some fighting around us as we neare Scotland, I know, but I could not see it, the cabin beir shuttered. Our pilot-captain ignored it and brougi his ship down on a totally dark field, using a beam, suppose, though I did not know nor care. I would have welcomed a crash. Then the lights outside went on and I saw that we had come to rest in an underground hangar.

I stayed in the ship. The Commandant came to see me to his quarters as his guest. I shook my head.

"I stay here," I said. "Orders. You are to treat this ship as United States soil, you know,"

He seemed miffed, but compromised by having dinner served for both of us in my ship.

There was a really embarra.s.sing situation the next day. I was commanded to appear for a Royal audience. But I had my instructions and I stuck to them. I was sitting on that cargo of dust until the President told me what to do with it. Late in the day I was called on by a member of Parliament-n.o.body admitted out loud that it was the Prime Minister-and a Mr. Windsor. The M.P. did most of the talking and I answered his questions. My other guest said very little and spoke slowly with some difficulty. But I got a very favorable impression of him. He seemed to be a man who was carrying a load beyond human strength and carrying it heroically.

There followed the longest period in my life. It was actually only a little longer than a week, but every minute of it had that split-second intensity of imminent disaster that comes just before a car crash. The President was using the time to try to avert the need to use the dust. He had two face-to-face television conferences with the new Fuehrer. The President spoke German fluently, which should have helped. He spoke three times to the warring peoples themselves, but it is doubtful if very many on the Continent were able to listen, the police regulations there being what they were.

The Amba.s.sador from the Reich was given a special demonstration of the effect of the dust. He was flown out over a deserted stretch of Western prairie and ~ lowed to see what a single dusting would do to a he] of steers. It should have impressed him and I thu that it did-n.o.body could ignore a visual demonstr tion!-but what report he made to his leader we nev knew.