Dr. Urth lifted himself out of the chair with a pleased puff and trotted to the door. 'It is always pleasant to see you. Inspector Davenport. Do come again. And remember the government can have the uranium, but I want the important thing: one giant silicony, alive and in good condition.' He was smiling.

'And preferably,' said Davenport, 'whistling.' Which he was doing himself as he walked out.

Afterword.

Of course, there is a catch about writing a mystery. You are apt to concentrate so bard on the mystery itself, on occasion, as to lose sight of important peripheral values. After this story first appeared, I received quite a bit of mail expressing interest in the silicony and, in some cases, finding fault with me for allowing it to die in so coldblooded a fashion. As I reread the story now, I must admit the readers are right. I showed a lack of sensitivity to the silicony's rather pathetic death because I was concentrating on his mysterious last words. If I had to do it over again, I would certainly be warmer in my treatment of the poor thing. I apologize.

This shows that even experienced writers don't always do the Right Thing, and can miss something that is bobbing up and down right at mustache level.

Foreword.

This next story is not, in the strictest sense of the word, a science fiction mystery, yet I include it. The reason is that science is closely and intimately involved with the mystery, and I hesitate to penalize it by non-inclusion merely because the science is of the present rather than of the future.

What's in a Name ?

If you think it's hard to get hold of potassium cyanide, think again. I stood there with a pound bottle in my hand. Brown glass, a nice clear label saying 'Potassium Cyanide CP' (the initials, I was told, meaning 'chemically pure') with a small skull and crossbones underneath.

The fellow who owned the bottle polished his glasses and blinked at me. He was Associate Professor Helmuth Rodney of Carmody University. He was of middle height, stocky, with a soft chin, plump lips, a budding paunch, a shock of brown hair, and a look of complete indifference to the fact that I was holding in my hand enough poison to kill a regiment.

I said, 'Do you mean to say this just stands on your shelf, Professor?'

He said in the kind of deliberate tone he probably used in lecturing his students, 'Yes, it always has, Inspector. Along with the rest of the chemicals in alphabetic order.'

I glanced about the cluttered room. Shelves lined the upper reaches of all the walls, and bottles, large and small, filled them all.

This one,' I pointed out, 'is poison.'

'A great many of them are,' he said with composure.

'Do you keep track of what you've got?'

'In a general way.' He rubbed his chin. 'I know I have that bottle.'

'But suppose someone came in here and helped himself to a spoonful of this stuff. Would you be able to tell ?'

Professor Rodney shook his head. 'I couldn't possibly.'

'Well, then, who could get into this laboratory ? It is kept locked?'

He said, 'It's locked when I leave in the evening, unless I forget. During the day, it isn't locked, and I'm in and out.'

'In other words. Professor, anyone could come in here, even someone from the street, walk off with some of the cyanide, and no one would ever know.'

'I'm afraid so.'

'Tell me. Professor, why do you keep this much cyanide in the place anyway ? To kill rats ?'

'Good heavens, no.' He seemed family repelled at the thought. 'Cyanide is sometimes used in organic reactions to form necessary intermediates, to provide a proper basic medium, to catalyze--'

'I see. I see. Now in what other labs is cyanide available in this way?'

'In most of them,' he answered at once. 'Even in the student labs. After all, it's a common chemical, routinely used in syntheses.'

'I wouldn't call its use today routine,' I said.

He sighed and said, 'No, I suppose not.' He added thoughtfully, They used to call them the "Library Twins." '

I nodded. I could see the reason for the nickname. The two girl librarians were very alike.

Not close up, of course. One had a small pointed chin on a round face, and the other had a square jaw and a long nose. Still, bend them over a desk and both had honey-blond hair parted in the middle with a similar wave. Look them quickly in the face and you would probably notice first wide-set eyes of about the same shade of blue. See them standing together at a moderate distance and you could see they were both of a height and both, probably, with the same brand and size uplift brassiere. Both had trim waists and neat legs. Today they had even dressed similarly. Both wore blue.

There was no confusing the two now, though. The one with the small chin and round face was full of cyanide, and quite dead.

The similarity was the first thing that struck me when I arrived with my partner, Ed Hathaway. There was one girl slumped in her chair and dead, her eyes open, one arm dangling straight down, with a broken teacup on the floor beneath like a period under an exclamation point. Her name, it turned out, was Louella-Marie Busch. There was a second girl, like the first one brought back to life, white and shaken, staring straight ahead and letting the police and their work flow about her without seeming to notice. Her name was Susan Morey.

The first question I asked was, 'Relatives?'

They weren't. Not even second cousins.

I looked about the library. There were whole shelves of books in similar bindings, then other shelves with books in another set of bindings. They were volumes of different research journals. In another room were stacks of what I found later to be textbooks, monographs, and older books. In the back was a special alcove containing recent numbers of unbound research periodicals in dull and closely printed paper covers. From wall to wall were long tables that might have seated a hundred people if all were fully occupied. Fortunately that wasn't the case.

We got the story out of Susan Morey in flat, toneless pieces.

Mrs. Nettler, the old Senior Librarian had taken off for the afternoon and had left the two girls in charge. That, apparently, was not unusual.

At two o'clock, give or take five minutes, Louella-Marie took herself into the back room behind the library desk. There, in addition to new books that awaited cataloguing, stacks of periodicals that awaited binding, reserved books that awaited their reservers, there was also a small hot-plate, a small kettle, and the fixings for weak tea.

Two o'clock tea was apparently usual, too.

I said, 'Did Louella-Marie prepare the tea every day?'

Susan looked at me out of her blank blue eyes. 'Sometimes Mrs. Nettler does, but usually Lou-Louella-Marie did.'

When the tea was ready, Louella-Marie emerged to say so and after a few moments the two retired.

'Both of you?' I asked sharply. 'Who took care of the library?'

Susan shrugged as though this were a minor point to worry about, and said, 'We can see out the door If anyone came to the desk, one of us could have gone out.'

'Did anyone come to the desk?'

'No one. It's intersession. Hardly anyone's around.'

By intersession she meant that the spring semester was over and the summer sessions had not yet started. I learned quite a bit about college life that day.

What was left of the story was little enough. The tea bags were already out of the gently steaming cups and the sugar had been added.

I interrupted. 'You both take sugar?'

Susan said slowly, 'Yes. But mine didn't have any.'

'No?'

'She never forgot before. She knows I take it. I just took a sip or two and I was going to reach for the sugar and tell her, you know, when--'

When Louella-Marie gave a queer strangled cry, dropped the cup, and was dead in a minute.

After that Susan screamed and eventually we came.

The routine passed smoothly enough. Photographs and fingerprints had been taken. The names and addresses of the men and women in the building were taken and they were sent home. Cause of death was obviously cyanide and the sugar bowl was the obvious villain. Samples were taken for official testing.

There had been six men in the library at the time of the murder. Five were students, who looked frightened, confused, or sick, depending, I suppose, on their personalities. The sixth was a middle-aged man, an outsider, who talked with a German accent and had no connection with the college at all. He looked frightened, confused, and sick, all three.

My sidekick, Hathaway, was leading them out of the library. The idea was to get them to the Co-educational Lounge and have them stay put till we could get to them in detail.

One of the students broke away and strode past me without a glance. Susan flew to meet him, clutching each sleeve above the elbow. 'Pete. Pete.'

Pete was built like a football player except that his profile looked as though he had never been within half a mile of the playing field. He was too good-looking for my taste, but then I get jealous easily.

Pete was looking past the girl, his face coming apart at the seams till its prettiness was drowned in uneasy horror. He said in a hoarse, choking way, 'How did Lolly come to...'

Susan gasped, 'I don't know. I don't know.' She kept trying to meet his eye.

Pete pulled away. He never looked at Susan once, kept staring over her shoulder. Then he responded to Hathaway's grip on his elbow and let himself be led away.

I said, 'Boyfriend?'

Susan tore her eyes from the departing student. 'What ?'

'Is he your boy friend?'

She looked down at her twisting hands. 'We've been out on dates.'

'How serious?'

She whispered, 'Pretty serious.'

'Does he know the other girl, too? He called her Lolly?'

Susan shrugged. 'Well...'

'Let's put it this way. Did he go out with her ?'

'Sometimes.'

'Seriously.'

She snapped, 'How should I know?'

'Come on, now. Was she jealous of you?'

'What's all this about?'

'Someone put the cyanide in the sugar and put the mixture in only one cup. Suppose Louella-Marie was jealous enough of you to try to poison you and leave herself a clear field with our friend Pete. And suppose she took the wrong teacup herself by mistake.'

Susan said, That's crazy. Louella-Marie wouldn't do such a thing.'

But her lips were thin, her eyes sparkled, and I can tell hate in a voice when I hear it.

Professor Rodney came into the library. He was the first man I had met on entering the building and my feelings toward him had grown no warmer.

He had begun by informing me that as senior faculty member present, he was in charge.

I said, 'I'm in charge now, Professor.'

He said, 'Of the investigation perhaps, Inspector, but it is I who am responsible to the Dean and I propose to fulfill my responsibilities.'

And although he hadn't the figure of an aristocrat, more like a shopkeeper, if you follow me, he managed to look at me as though there were a microscope between as with himself on the large side.

Now he said, 'Mrs. Nettler is in my office. She heard the news bulletin, apparently, and came at once. She is quite agitated. You will see her?' He made it sound like an order.

'Bring her in. Professor.' I made it sound like permission.

Mrs. Nettler was in the usual quandary of the average old lady. She didn't know whether to be horrified or fascinated at the closeness with which death had struck. Horror won out after she looked into the inner office and noticed what was left of the tea things. The body was gone by then, of course.

She flopped into a chair and began crying. 'I had tea here myself,' she moaned. 'It might have been ...'

I said as quietly and soothingly as I could manage, 'When did you drink tea here, Mrs. Nettler?'

She turned in her seat, looked up. 'Why-why, just after one, I think. I offered Professor Rodney a cup, I remember. It was just after one, Professor Rodney, wasn't it?'

A trace of annoyance crossed Rodney's plump face. He said to me, 'I was here a moment just after lunch to consult a reference. Mrs, Nettler did offer a cup. I was too busy, I'm afraid, to accept or to note the time exactly.'

I grunted and turned back to the old lady. 'Do you take sugar, Mrs. Nettler?'