Poirot asked no more questions.
Our next move was to visit Dr. Quentin.
His story was substantially the same as he had told at the inquest, and he had little to add to it.
He received us in his surgery, having just come to the end of his consulting patients.
He seemed an intelligent man.
A certain primness of manner went well with his pince-nez, but I fancied that he would be thoroughly modern in his methods.
"I wish I could remember about the window," he said frankly. "But it's dangerous to think back, one becomes quite positive about something that never existed.
That's psychology, isn't it, M. Poirot?
You see, I've read all about your methods, and I may say I'm an enormous admirer of yours.
No, I suppose it's pretty certain that the Chinaman put the powdered opium in the curry, but he'll never admit it, and we shall never know why.
But holding a man down in a fire - that's not in keeping with our Chinese friend's character, it seems to me."
I commented on this last point to Poirot as we walked down the main street of Market Handford.
"Do you think he let a confederate in?" I asked. "By the way, I suppose Japp can be trusted to keep an eye on him?" (The Inspector had passed into the police station on some business or other.) "The emissaries of the Big Four are pretty spry."
"Japp is keeping an eye on both of them," said Poirot grimly. "They have been closely shadowed ever since the body was discovered."
"Well, at any rate we know that Gerald Paynter had nothing to do with it."
"You always know so much more than I do, Hastings, that it becomes quite fatiguing."
"You old fox," I laughed. "You never will commit yourself."
"To be honest, Hastings, the case is now quite clear to me - all but the words, Yellow Jasmine - and I am coming to agree with you that they have no bearing on the crime.
In a case of this kind, you have got to make up your mind who is lying.
I have done that.
And yet -" He suddenly darted from my side and entered an adjacent bookshop.
He emerged a few minutes later, hugging a parcel.
Then Japp rejoined us, and we all sought quarters at the inn.
I slept late the next morning.
When I descended to the sitting-room reserved for us, I found Poirot already there, pacing up and down, his face contorted with agony.
"Do not converse with me," he cried, waving an agitated hand. "Not until I know that all is well - that the arrest is made.
Ah! but my psychology has been weak.
Hastings, if a man writes a dying message, it is because it is important.
Every one has said -
'Yellow Jasmine'.
There is yellow jasmine growing up the house - it means nothing.'"
"Well, what does it mean?
Just what it says.
Listen." He held up a little book he was holding. "My friend, it struck me that it would be well to inquire into the subject.
What exactly is yellow jasmine?
This little book has told me.
Listen."
He read. "'Gelsemini Radix. Yellow Jasmine.
Composition: Alkaloids gelseminine C22H26N2O3, a potent poison acting like coniine; gelsemine C12H14NO2, acting like strychnine; gelsemic acid, etc.
Gelsemium is a powerful depressant to the central nervous system.
At a late stage in its action it paralyses the motor nerve endings, and in large doses causes giddiness and loss of muscular power.
Death is due to paralysis of the respiratory centre.'
"You see, Hastings?
At the beginning I had an inkling of the truth when Japp made his remark about a live man being forced into the fire.
I realised then that it was a dead man who was burned."
"But why?
What was the point?"
"My friend, if you were to shoot a man, or stab a man after he were dead, or even knock him on the head, it would be apparent that the injuries were inflicted after death.
But with his head charred to a cinder, no one is going to hunt about for obscure causes of death, and a man who has apparently just escaped being poisoned at dinner, is not likely to be poisoned just afterwards.
Who is lying, that is always the question?