IN the salon I found the examining magistrate busily interrogating the old gardener Auguste. Poirot and the commissary, who were both present, greeted me respectively with a smile and a polite bow. I slipped quietly into a seat. M. Hautet was painstaking and meticulous in the extreme, but did not succeed in eliciting anything of importance.

The gardening gloves Auguste admitted to be his. He wore them when handling a certain species of primula plant which was poisonous to some people. He could not say when he had worn them last. Certainly he had not missed them. Where were they kept? Sometimes in one place, sometimes in another. The spade was usually to be found in the small tool-shed. Was it locked? Of course it was locked.

Where was the key kept? Parbleu, it was in the door of course. There was nothing of value to steal. Who would have expected a party of bandits, or assassins? Such things did not happen in Madame la Vicomtesse's time.

M. Hautet signifying that he had finished with him, the old man withdrew, grumbling to the last. Remembering Poirot's unaccountable insistence on the footprints in the flowerbeds, I scrutinized him narrowly as he gave his evidence.

Either he had nothing to do with the crime or he was a consummate actor. Suddenly just as he was going out of the door an idea struck me.

'Pardon, Monsieur Hautet,' I cried, 'but will you permit me to ask him one question?'

'But certainly monsieur.'

Thus encouraged, I turned to Auguste. 'Where do you keep your boots?'

'On my feet,' growled the old man. 'Where else?'

'But when you go to bed at night?'

'Under my bed.'

'But who cleans them?'

'Nobody. Why should they be cleaned? Is it that I promenade myself on the front like a young man? On Sunday I wear the Sunday boots, but otherwise-' He shrugged his shoulders.

I shook my head, discouraged.

'Well, well,' said the magistrate, 'we do not advance very much. Undoubtedly we are held up until we get the return cable from Santiago. Has anyone seen Giraud? In verity that one lacks politeness! I have a very good mind to send for him and [missing].

'You will not have to send far.'

The quiet voice startled us. Giraud was standing outside looking in through the open window.

He leapt lightly into the room and advanced to the table. 'Here I am, at your service. Accept my excuses for not presenting myself sooner.'

'Not at all-not at all!' said the magistrate, rather confused.

'Of course I am only a detective,' continued the other. 'I know nothing of interrogatories. Were I conducting one, I should be inclined to do so without an open window. Anyone standing outside can so easily hear all that passes. But no matter.'

M. Hautet flushed angrily. There was evidently going to be no love lost between the examining magistrate and the detective in charge of the case. They had fallen foul of each ether at the start. Perhaps in any event it would have been much the same. To Giraud, all examining magistrates were fools, and to M. Hautet, who took himself seriously, the casual manner of the Paris detective could not fail to give offence.

'Et bien, Monsieur Giraud,' said the magistrate rather sharply. 'Without doubt you have been employing your time to a marvel! You have the names of the assassins for us, have you not? And also the precise spot where they find themselves now?'

Unmoved by this irony, M. Giraud replied: 'I know at least where they have come from.'

Giraud took two small objects from his pocket and laid them down on the table. We crowded round. The objects were very simple ones: the stub of a cigarette and an unlighted match. The detective wheeled round on Poirot.

'What do you see there?' he asked.

There was something almost brutal in his tone. It made my cheeks flush. But Poirot remained unmoved. He shrugged his shoulders.

'A cigarette end and a match.'

'And what does that tell you?'

Poirot spread out his hands. 'It tells me-nothing.'

'Ah!' said Giraud, in a satisfied voice. 'You haven't made a study of these things. That's not an ordinary match-not in this country at least. It's common enough in South America. Luckily it's unlighted. I mightn't have recognized it otherwise. Evidently one of the men threw away his cigarette and lit another, spilling one match out of the box as he did so.'

'And the other match?' asked Poirot.

'Which match?'

'The one he did light his cigarette with. You have found that also?'

'No.'

'Perhaps you didn't search very thoroughly.'

'Not search thoroughly-' For a moment it seemed as though the detective was going to break out angrily, but with an effort he controlled himself. 'I see you love a joke, Monsieur Poirot. But in any case, match or no match, the cigarette end would be sufficient. It is a South American cigarette with liquorice pectoral paper.'

Poirot bowed. The commissary spoke: 'The cigarette end and match might have belonged to Monsieur Renauld. Remember, it is only two years since he returned from South America.'

'No,' replied the other confidently. 'I have already searched among the effects of Monsieur Renauld. The cigarettes he smoked and the matches he used are quite different.'

'You do not think it odd,' asked Poirot, 'that these strangers should come unprovided with a weapon, with gloves, with a spade, and that they should so conveniently find all these things?'

Giraud smiled in a rather superior manner. 'Undoubtedly it is strange. Indeed, without the theory that I hold, it would be inexplicable.'

'Aha!' said M. Hautet. 'An accomplice within the house!'

'Or outside it,' said Giraud, with a peculiar smile.

'But someone must have admitted them. We cannot allow that, by an unparalleled piece of good fortune, they found the door ajar for them to walk in?'

'The door was opened for them; but it could just as easily be opened from outside-by someone who possessed a key.'

'But who would possess a key?'

Giraud shrugged his shoulders. 'As for that, no one who possesses one is going to admit the fact if he can help it. But several people might have had one. Monsieur Jack Renauld, the son, for instance. It is true that he is on his way to South America, but he might have lost the key or had it stolen from him. Then there is the gardener-he has been here many years. One of the younger servants may have a lover. It is easy to take an impression of a key and have one cut. There are many possibilities. Then there is another person who, I should judge, is exceedingly likely to have such a thing.'

'Who is that?'

'Madame Daubreuil,' said the detective.

'Eh, eh!' said the magistrate. 'So you have heard about that, have you?'

'I hear everything,' said Giraud imperturbably.

'There is one thing I could swear you have not heard,' said Hautet, delighted to be able to show superior knowledge, and without more ado he retailed the story of the mysterious visitor the night before. He also touched on the cheque made out to 'Duveen', and finally handed Giraud the letter signed 'Bella'.

'All very interesting. But my theory remains unaffected.'

'And your theory is?'

'For the moment I prefer not to say. Remember, I am only just beginning my investigations.'

'Tell me one thing, Monsieur Giraud' said Poirot suddenly. 'Your theory allows for the door being opened. It does not explain why it wasn't open. When they departed, would it not have been natural for them to close it behind them. If a sergent had chanced to come up to the house as is sometimes done to see that all is well, they might have been discovered and overtaken almost at once.'

'Bah! They forgot it. A mistake, I grant you.'

Then to my surprise Poirot uttered almost the same words a he had uttered to Bex the previous evening: 'I do not agree with you. The door being left open was the result of either design or necessity, and any theory that does not admit that fact is bound to prove vain.'

We all regarded the little man with a good deal of astonishment. The confession of ignorance drawn from him over the match end had, I thought, been bound to humiliate him, but here he was self-satisfied as ever, lying down the how to Giraud without a tremor.

The detective twisted his moustache, eyeing my friend in a somewhat bantering fashion. 'You don't agree with me, eh? Well, what strikes you particularly about the case? Let's hear your views.'

'One thing presents itself to me as being significant. Tell me, Monsieur Giraud, does nothing strike you as familiar about this case? Is there nothing it reminds you of?'

'Familiar? Reminds me of? I can't say off-hand. I don't think so, though.'

'You are wrong,' said Poirot quietly. 'A crime almost precisely similar has been committed before.'

'When? And where?'

'Ah, that, unfortunately,. I cannot for the moment remember, but I shall do so. I had hoped you might be able to assist me.'

Giraud snorted incredulously. 'There have been many affairs of masked men. I cannot remember the details of them all. The crimes all resemble each other more or less.'

'There is such a thing as the individual touch.' Poirot suddenly assumed his lecturing manner, and addressed us collectively. 'I am speaking to you now of the psychology of crime. Monsieur Giraud knows quite well that each criminal has his particular method, and that the police, when called in to investigate, say, a case of burglary, can often make a shrewd guess at the offender, simply by the peculiar methods he has employed. (Japp would tell you the same, Hastings.) Man is an unoriginal animal. Unoriginal within the law in his daily respectable life, equally unoriginal outside the law. If a man commits a crime, any other crime he commits will resemble it closely. The English murderer who disposed of his wives in succession by drowning them in their baths was a case in point. Had he varied his methods, he might have escaped detection to this day. But he obeyed the common dictates of human nature, arguing that what had once succeeded would succeed again, and he paid the penalty of his lack of originality.'

'And the point of all this?' sneered Giraud.

'That, when you have two crimes precisely similar in design and execution, you find the same brain behind them both. I am looking for that brain, Monsieur Giraud, and I shall find it. Here we have a true clue-a psychological clue. You may know all about cigarettes and match ends, Monsieur Giraud, but I, Hercule Poirot, know the mind of man.'

Giraud remained singularly unimpressed.

'For your guidance,' continued Poirot, 'I will also advise you of one fact which might fail to be brought to your notice. The wristwatch of Madame Renauld, on the day following the tragedy, had gained two hours.'