It is possible that Mrs. Hubbard revived rather quicker with these methods than she might otherwise have done. A few minutes later she was sitting up, sipping cognac from a glass proffered by the attendant, and talking once more.

"I just can't say how terrible it was. I don't suppose anybody on this train can understand my feelings. I've always been vurry, vurry sensitive ever since a child. The mere sight of blood -- ugh -- why even now I come over queer when I think about it."

With more vigour than chivalry, M. Bouc deposited the fainting lady with her head on the table. Dr. Constantine yelled for one of the restaurant attendants, who came at a run.

"Keep her head so," said the doctor. "If she revives give her a little cognac. You understand?"

The attendant proffered the glass again. "Encore un peu, Madame."

"D'you think I'd better? I'm a lifelong teetotaller. I just never touch spirits or wine at any time. All my family are abstainers. Still perhaps as this is only medical --"

Then he hurried off after the other two. His interest lay wholly in the crime -- swooning middle-aged ladies did not interest him at all.

In the meantime Poirot and M. Bouc, closely followed by Dr. Constantine, had hurried out of the restaurant car and along the corridor of the Stamboul coach towards Mrs. Hubbard's compartment.

Every traveller on the train seemed to be congregated outside the door. The conductor, a harrassed look on his face, was keeping them back.

"Let me pass, if you please," said M. Bouc.

Squeezing his rotundity past the obstructing passengers, he entered the compartment, Poirot close behind him.

"I am glad you have come Monsieur," said the conductor with a sigh of relief. "Everyone has been trying to enter. The American lady -- such screams as she gave -- ma foi! I thought she too had been murdered! I came at a run and there she was screaming like a mad woman, and she cried out that she must fetch you and she departed, screeching at the top of her voice and telling everybody whose carriage she passed what had occurred."

She sipped once more.

"Mais il n'y a rien à voir," he said, and repeated the sentiment in several other languages.

Hanging on the handle of the door that gave access to the next compartment was a large-size checked rubber sponge bag. Below it on the floor, just where it had fallen from Mrs. Hubbard's hand, was a straightbladed dagger -- a cheap affair, sham Oriental, with an embossed hilt and a tapering blade. The blade was stained with patches of what looked like rust.

The doctor examined it.

"Yes," he murmured. "There is no mistake. Here is our missing weapon all right -- eh, docteur?"

"It is the weapon all right," he said. "It would account for any of the wounds."

He added, with a gesture of the hand: "It is in there, Monsieur. I have not touched it."

"I implore you, my friend, do not say that." The doctor looked astonished.

"You need not be so careful," said Poirot. "There will be no fingerprints on it save those of Mrs. Hubbard."

Poirot picked it up delicately.

Constantine's examination did not take long.

"Already we are heavily overburdened by coincidence. Two people decide to stab M. Ratchett last night. It is too much of a good thing that each of them should select an identical weapon."

"As to that, the coincidence is not, perhaps, so great as it seems," said the doctor. "Thousands of these sham Eastern daggers are made and shipped to the bazaars of Constantinople."

"We locked it from the other side, you remember," said the doctor.

"That is true," said Poirot absently. He seemed to be thinking about something else. His brow was furrowed as though in perplexity.

"You console me a little, but only a little," said Poirot. He looked thoughtfully at the door in front of him, then, lifting off the sponge bag, he tried the handle. The door did not budge. About a foot above the handle was the door bolt, Poirot drew it back and tried again, but still the door remained fast.

"It agrees, does it not?" said M. Bouc. "The man passes through this carriage. As he shuts the communicating door behind him he feels the sponge bag. A thought comes to him and he quickly slips the bloodstained knife inside. Then, all unwitting that he has awakened Mrs. Hubbard, he slips out through the other door into the corridor."

"As you say," murmured Poirot. "That is how it must have happened." But the puzzled look did not leave his face.

"But what is it?" demanded M. Bouc. "There is something, is there not, that does not satisfy you?"

"The same point does not strike you? No, evidently not. Well, it is a small matter."

The conductor looked into the carriage. "The American lady is coming back."

"But, Madame --"

Poirot darted a quick look at him.

"I'm just going to say one thing right out," she said breathlessly as she arrived in the doorway. "I'm not going on any longer in this compartment! Why, I wouldn't sleep in it tonight if you paid me a million dollars."

Dr. Constantine looked rather guilty. He had, he felt, treated Mrs. Hubbard rather cavalierly. But she had no reproaches for him. Her energies were concentrated on another matter.

"I know what you are going to say, and I'm telling you right now that I won't do any such thing! Why, I'd rather sit up all night in the corridor." She began to cry. "Oh! if my daughter could only know -- if she could see me now, why --"

Mrs. Hubbard lowered her handkerchief. "Is that so? Oh, I feel better right away. But surely it's all full up, unless one of the gentlemen --"

Poirot interrupted firmly. "You misunderstand, Madame. Your demand is most reasonable. Your baggage shall be changed at once to another compartment."

M. Bouc spoke. "Your baggage, Madame, shall be moved out of this coach altogether. You shall have a compartment in the next coach which was put on at Belgrade."

"Why, that's splendid. I'm not an out of the way nervous woman, but to sleep in that compartment next door to a dead man --" She shivered. "It would drive me plumb crazy."

"No," said Poirot before his friend could reply. "I think it would be better for Madame to have a different number altogether. The No. 12, for instance."

The conductor seized the luggage. Mrs. Hubbard turned gratefully to Poirot.

"Michel," called M. Bouc. "Move this baggage into a vacant compartment in the Athens-Paris coach."

"Bien, Monsieur."

"Yes, Monsieur -- the same one as this -- the No. 3?"

Mrs. Hubbard was escorted by the three men to her new home. She looked round her happily. "This is fine."

"That's vurry kind and delicate of you. I appreciate it, I assure you."

"Do not mention it, Madame. We will come with you and see you comfortably installed."

"It suits you, Madame? It is, you see, exactly like the compartment you have left."

"At any rate, Madame, you are quite happy and contented now?"

"Madame," said M. Bouc, "we are all in the same case -- every one of us."

"That's so -- only it faces the other way. But that doesn't matter, for these trains go first one way and then the other. I said to my daughter, 'I want a carriage facing the engine,' and she said, 'Why, Momma, that'll be no good to you, for if you go to sleep one way, when you wake up the train's going the other.' And it was quite true what she said. Why, last evening we went into Belgrade one way and out the other."

"Well, no, I wouldn't say that. Here we are stuck in a snowdrift and nobody doing anything about it, and my boat sailing the day after tomorrow."

"No, because of the sponge bag. Oh, my, I shall have to get a new sponge bag. It makes me feel sick in my stomach to look at this one."

"Well, that's true," admitted Mrs. Hubbard. "But nobody else has had a murderer walking right through their compartment in the middle of the night."

"What still puzzles me, Madame," said Poirot, "is how the man got into your compartment if the communicating door was bolted as you say. You are sure that it was bolted?"

"Why, that's just what I've been telling you!"

"Why, the Swedish lady tried it before my eyes."

"Let us just reconstruct that little scene. You were lying in your bunk -- so -- and you could not see for yourself, you say?"

Poirot picked up the sponge bag and hung it on the handle of the communicating door into the next carriage.

"Précisément -- I see," he said. "The bolt is just underneath the handle -- the sponge bag masks it. You could not see from where you were lying whether the bolt were turned or not."

"And the Swedish lady, Miss Ohlsson, stood so, between you and the door. She tried it and told you it was bolted."

"That's so."

"No. I sailed right to Stamboul, and a friend of my daughter's -- Mr. Johnson (a perfectly lovely man; I'd like to have you know him)-- met me and showed me all round Stamboul, which I found a very disappointing city -- all tumbling down. And as for those mosques and putting on those great shuffling things over your shoes -- where was I?"

"Well I guess that would be rather stupid of her."

"You were saying that Mr. Johnson met you."

"All the same, Madame, she may have made an error. You see what I mean." Poirot seemed anxious to explain. "The bolt is just a projection of metal -- so. Turned to the right the door is locked, left straight, it is not. Possibly she merely tried the door, and as it was locked on the other side she may have assumed that it was locked on your side."

"Madame, the most kind, the most amiable are not always the cleverest."

"That's so, and he saw me on board a French Messagerie boat for Smyrna, and my daughter's husband was waiting right on the quay. What he'll say when he hears about all this! My daughter said this would be just the safest, easiest way imaginable. 'You just sit in your carriage,' she said, 'and you get right to Parrus and there the American Express will meet you.' And, oh dear, what am I to do about cancelling my steamship passage? I ought to let them know. I can't possibly make it now. This is just too terrible --"

"That's so, of course."

"By the way, Madame, did you travel out to Smyrna this way?"

"Mercy! Perhaps you'd better! I just couldn't bear to get any more surprises of that kind."

"Excellent. You must revive your forces."

"I don't know that I'm so set on tea," said Mrs. Hubbard tearfully. "That's more an English habit."

"We are about to commence a search of all the passengers' luggage. I do not want to remind you of an unpleasant experience, but your sponge bag -- remember."

"Whatever for?"

The examination was quickly over. Mrs. Hubbard was travelling with the minimum of luggage -- a hat box, a cheap suitcase, and a well-burdened travelling bag. The contents of all three were simple and straightforward, and the examination would not have taken more than a couple of minutes had not Mrs. Hubbard delayed matters by insisting on due attention being paid to photographs of "My daughter" and two rather ugly children --"My daughter's children. Aren't they cunning?"

"But first, Madame, a little matter of routine. You permit that I make a search of your baggage?"

Poirot, who had been fidgeting slightly, seized his opportunity.

"My, what a funny expression."

"That cognac's made my head feel mighty funny. I think I would like some coffee."

"Coffee, then, Madame. You need some stimulant."

"You have had a shock, Madame. The restaurant attendant shall be instructed to bring you along some tea and some biscuits."

Mrs. Hubbard showed signs of tears once more.