There was an uneasy stir.

Urth said at once, 'No need to be afraid of the psycho-probe. Proper handling is safe, particularly if a man offers himself voluntarily. When damage is done, it is usually because of unnecessary resistance, a kind of mental tearing, you know. So if the guilty man will voluntarily confess, place himself in my hands--'

Talliaferro laughed. The sudden noise rang out sharply in the dim quiet of the room. The psychology was so transparent and artless.

Wendell Urth looked almost bewildered at the reaction and stared earnestly at Talliaferro over his glasses. He said, 'I have enough influence with the police to keep the probing, entirely confidential.'

Ryger said savagely, 'I didn't do it.'

Kaunas shook his head.

Talliaferro disdained any answer.

Urth sighed. 'Then I shall have to point out the guilty man. It will be traumatic. It will make things harder.' He tightened the grip on his belly and his fingers twitched. 'Dr. Talliaferro indicated that the film was hidden on the outer window sill so that it might remain safe from discovery and from harm. I agree with him.'

'Thank you,' said Talliaferro dryly.

'However, why should anyone think that an outer window sill is a particularly safe hiding place? The police would certainly look there.

'Even in the absence of the police it was discovered. Who would tend to consider anything outside a building as particularly safe? Obviously some person who has lived a long time on an airless world has had it drilled into him that no one goes outside an enclosed place without detailed precautions.

To someone on the Moon, for instance, anything hidden outside a Lunar Dome would be comparatively safe. Men venture out only rarely and then only on specific business. So he would overcome the hardship of opening a window and exposing himself to what he would subconsciously consider a vacuum for the sake of a safe hiding place. The reflex thought, Outside an inhabited structure is safe, would do the trick.'

Talliaferro said between clenched teeth, 'Why do you mention the Moon, Dr. Urth ?'

Urth said blandly, 'Only as an example. What I've said so far applies to all three of you. But now comes the crucial point, the matter of the dying night.'

Talliaferro frowned. 'You mean the night Villiers died?'

'I mean any night. See here, even granted that an outer window sill was a safe hiding place, which of you would be mad enough to consider it a safe hiding place for a piece of unexposed film ? Scanner film isn't very sensitive, to be sure, and is made to be developed under all sorts of hit-and-miss conditions. Diffuse nighttime illumination wouldn't seriously affect it, but diffuse daylight would ruin it in a few minutes, and direct sunlight would ruin it at once. Everyone knows that.'

Mandel said, 'Go ahead, Urth. What is this leading to?'

'You're trying to rush me,' said Urth, with a massive pout. 'I want you to see this clearly. The criminal wanted, above all, to keep the film safe. It was his only record of something of supreme value to himself and to the world. Why would he put it where it would inevitably be ruined almost immediately by the morning Sun? Only because he did not expect the morning Sun ever to come. He thought the night, so to speak, was immortal.

'But nights aren't immortal. On Earth they die and give way to daytime. Even the six-month polar night is a dying night eventually. The nights on Ceres last only two hours; the nights on the Moon last two weeks. They are dying nights too, and Drs. Talliaferro and Ryger know that day must always come.'

Kaunas rose. 'But wait--'

Wendell Urth faced him full. 'No longer any need to wait, Dr. Kaunas. Mercury is the only sizable object in the Solar System that turns only one face to the Sun. Even taking libration into account, fully three-eights of its surface is true dark-side and never sees the Sun. The Polar Observatory is at the rim of that dark-side. For ten years you have grown used to the fact that nights are immortal, that a surface in darkness remains eternally in darkness, and so you entrusted unexposed film to Earth's night, forgetting in your excitement that nights must die--'

Kaunas came forward. 'Wait--'

Urth was inexorable. 'I am told that when Mandel adjusted the polarizer in Villiers' room, you screamed at the sunlight. Was that your ingrained fear of the Mercurian Sun, or your sudden realization of what sunlight meant to your plans? You rushed forward. Was that to adjust the polarizer, or to stare at the ruined film ?'

Kaunas fell to his knees. 'I didn't mean it. I wanted to speak to him, only to speak to him, and he screamed and collapsed. I thought he was dead and the paper was under his pillow and it all just followed. One thing led on to another and before I knew it I couldn't get out of it anymore. But I meant none of it. I swear it.'

They had formed a semicircle about him and Wendell Urth stared at the moaning Kaunas with pity in his eyes.

An ambulance had come and gone. Talliaferro finally brought himself to say stiffly to Mandel, 'I hope, sir, there will be no hard feelings for anything said here.'

And Mandel had answered as stiffly, 'I think we had all better forget as much as possible of what has happened during the last twenty-four hours.'

They were standing in the doorway, ready to leave, and Wendell Urth ducked his smiling head and said, 'There's the question of my fee, you know.'

Mandell looked at him with a startled expression.

'Not money,' said Urth at once. 'But when the first mass transference setup for humans is established, I want a trip arranged for me right away.'

Mandel continued to look anxious. 'Now, wait. Trips through outer space are a long way off.'

Urth shook his head rapidly. 'Not outer space. Not at all. I would like to step across to Lower Falls, New Hampshire.'

'All right. But why?'

Urth looked up. To Talliaferro's outright surprise, the extraterrologist's face wore an expression compounded equally of shyness and eagerness.

Urth said, 'I once-quite a long time ago-knew a girl there. It's been many years-but I sometimes wonder...'

Afterword.

Some readers may realize that this story, first published in 1956, has been overtaken by events. In 1965, astronomers discovered that Mercury does not keep one side always to the Sun, but has a period of rotation of about fifty-four days, so that all parts of it are exposed to sunlight at one time or another. Well, what can I do except say that I wish astronomers would get things right to begin with? And I certainly refuse to change the story to suit their whims.

Foreword.

This item is not strictly a mystery in the usual sense of the word, or even a story in the usual sense of the word. I don't know how to describe it, except perhaps as a good-natured satire on scientific research. I received more mail alter its publication than alter any other item of comparable length. A particularly pleasant memory is that of receiving a telephone call from a man who spoke with a strong Central European accent. He said be was in Boston for a convention and wanted to thank me lor the pleasure 'Pate de Foie Gras' had given him, since it so amusingly and effectively poked knowledgeable fun at science. I tried to get his name, but he wouldn't give it to me. He was afraid, I suspect, that his reputation might suffer if it were found he read science fiction. If he is secretly reading this book and recognizes himself, I would like to assure him that he has plenty of company and can take off that plain wrapper. Honest!

Pate de Foie Gras.

I couldn't tell you my real name if I wanted to, and, under the circumstances, I don't want to.

I'm not much of a writer myself, so I'm having Isaac Asimov write this up for me. I've picked him for several reasons. First, he's a biochemist, so he understands what I tell him; some of it, anyway. Secondly, he can write; or at least he has published considerable fiction, which may not, of course, be the same thing.

I was not the first person to have the honor of meeting The Goose. That belongs to a Texas cotton farmer named Ian Angus MacGregor, who owned it before it became government property.

By summer of 1955 he had sent an even dozen of letters to the Department of Agriculture requesting information on the hatching of goose eggs. The department sent him all the booklets on hand that were anywhere near the subject, but his letters simply got more impassioned and freer in their references to his 'friend,' the local congressman.

My connection with this is that I am in the employ of the Department of Agriculture. Since I was attending a convention at San Antonio in July of 1955, my boss asked me to stop off at MacGregor's place and see what I could do to help him. We're servants of the public and besides we had finally received a letter from MacGregor's congressman.

On July 17,1955, I met The Goose.

I met MacGregor first. He was in his fifties, a tall man with a lined face full of suspicion. I went over all the information he had been given, then asked politely if I might see his geese.

He said, 'Its not geese, mister; it's one goose.'

I said, 'May I see the one goose?'

'Rather not.'

'Well, then, I can't help you any further. If it's only one goose, then there's just something wrong with it. Why worry about one goose? Eat it.'

I got up and reached for my hat.

He said, 'Wait!' and I stood there while his lips tightened and his eyes wrinkled and he had a quiet fight with himself. 'Come with me.'

I went out with him to a pen near the house, surrounded by barbed wire, and a locked gate to it, and holding one goose-The Goose.

That's The Goose,' he said. The way he said it, I could hear the capitals.

I stared at it. It looked like any other goose, fat, self-satisfied, and short-tempered.

MacGregor said, 'And here's one of its eggs. It's been in the incubator. Nothing happens.' He produced it from a capacious overall pocket. There was a queer strain about his manner of holding it.

I frowned. There was something wrong with the egg. It was smaller and more spherical than normal.

MacGregor said, Take it.'

I reached out and took it. Or tried to. I gave it the amount of heft an egg like that ought to deserve and it just sat where it was. I had to try harder and then up it came.

Now I knew what was queer about the way MacGregor held it. It weighed nearly two pounds.

I stared at it as it lay there, pressing down the palm of my hand, and MacGregor grinned sourly. 'Drop it,' he said.

I just looked at him, so he took it out of my hand and dropped it himself.

It hit soggy. It didn't smash. There was no spray of white and yolk. It just lay where it fell with the bottom caved in.

I picked it up again. The white eggshell had shattered where the egg had struck. Pieces of it had naked away and what shone through was a dull yellow in color. My hands trembled. It was all I could do to make my fingers work, but I got some of the rest of the shell flaked away, and stared at the yellow.

I didn't have to run any analyses. My heart told me.

I was face to face with The Goose!

The Goose That Laid The Golden Eggs! My first problem was to get MacGregor to give up that golden egg. I was almost hysterical about it.

I said, 'I'll give you a receipt. I'll guarantee you payment. I'll do anything in reason.'

'I don't want the government butting in,' he said stubbornly.

But I was twice as stubborn and in the end I signed a receipt and he dogged me out to my car and stood in the road as I drove away, following me with his eyes.

The head of my section at the Department of Agriculture is Louis P. Bronstein. He and I are on good terms and I felt I could explain things without being placed under immediate observation. Even so, I took no chances. I had the egg with me and when I got to the tricky part, I just laid it on the desk between us.

I said, 'It's a yellow metal and it could be brass only it isn't because it's inert to concentrated nitric acid.'

Bronstein said, 'It's some sort of hoax. It must be.'

'A hoax that uses real gold ? Remember, when I first saw this thing, it was covered completely with authentic unbroken eggshell. It's been easy to check a piece of the egg shell. Calcium carbonate.'

Project Goose was started. That was July 20, 1955.

I was the responsible investigator to begin with and remained in titular charge throughout., though matters quickly got beyond me.

We began with the one egg. Its average radius was 35 millimeters (major axis, 72 millimeters; minor axis, 68 millimeters). The gold shell was 2.45 millimeters in thickness. Studying other eggs later on, we found this value to be rather high. The average thickness turned out to be 2.1 millimeters.

Inside was egg. It looked like egg and it smelled like egg.

Aliquots were analyzed and the organic constituents were reasonably normal. The white was 9.7 per cent albumin. The yolk had the normal complement of vitellin, cholesterol, phospholipid, and carotenoid. We lacked enough material to test for trace constituents, but later on with more eggs at our disposal we did and nothing unusual showed up as far as contents of vitamins, coenzymes, nucleotides, sulfhydryl groups, et cetera, et cetera were concerned.

One important gross abnormality that showed was the egg's behavior on heating. A small portion of the yolk, heated, 'hard-boiled' almost at once. We fed a portion of the hard-boiled egg to a mouse. It survived.

I nibbled at another bit of it. Too small a quantity to taste, really, but it made me sick. Purely psychosomatic, I'm sure.

Boris W. Finley, of the Department of Biochemistry of Temple University-a department consultant-supervised these tests.

He said, referring to the hard-boiling, The ease with which the egg proteins are heat-denatured indicates a partial denaturation to begin with and, considering the nature of the shell, the obvious guilt would lie at the door of heavy-metal contamination.'

So a portion of the yolk was analyzed for inorganic constituents, and it was found to be high in chloraurate ion, which is a singly charged ion containing an atom of gold and four of chlorine, the symbol for which is AuCl4-. (The 'Au' symbol for gold comes from the fact that the Latin word for gold is 'aurum.') When I say the chloraurate ion content was high, I mean it was 3.2 parts per thousand, or 0.32 per cent. That's high enough to form insoluble complexes of 'gold protein' which would coagulate easily.

Finley said, 'It's obvious this egg cannot hatch. Nor can any other such egg. It is heavy-metal poisoned. Gold may be more glamorous than lead but it is just as poisonous to proteins.'

I agreed gloomily. 'At least it's safe from decay, too.'

'Quite right. No self-respecting bug would live in this chlorauriferous soup.'

The final spectrographic analysis of the gold of the shell came in. Virtually pure. The only detectable impurity was iron which amounted to 0-25 per cent of the whole. The iron content of the egg yolk had been twice normal, also. At the moment, however, the matter of the iron was neglected.

One week after Project Goose was begun, an expedition was sent into Texas. Five biochemists went-the accent was still on biochemistry, you see-along with three truckloads of equipment, and a squadron of army personnel. I went along too, of course.

As soon as we arrived, we cut MacGregor's farm off from the world.

That was a lucky thing, you know-the security measures we took right from the start. The reasoning was wrong, at first, but the results were good.

The Department wanted Project Goose kept quiet at the start simply because there was always the thought that this might still be an elaborate hoax and we couldn't risk the bad publicity if it were. And if it weren't a hoax, we couldn't risk the newspaper hounding that would definitely result over any goose-and-golden-egg story.

It was only well after the start of Project Goose, well after our arrival at MacGregor's farm, that the real implications of the matter became clear.

Naturally MacGregor didn't like the men and equipment settling down all about him. He didn't like being told The Goose was government property. He didn't like having his eggs impounded.