"'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? I decided to believe Ah Ling—"
"What!" I exclaimed.
"You are surprised, Hastings? Ah Ling knew of the existence of the Big Four, that was evident—so evident that it was clear he knew nothing of their association with the crime until that moment. Had he been the murderer, he would have been able to retain his impassive face perfectly. So I decided then, to believe Ah Ling, and I fixed my suspicions on Gerald Paynter. It seemed to me that Number Four would have found an impersonation of a long lost nephew very easy."
"What!" I cried. "Number Four?"
"No, Hastings, not Number Four. As soon as I had read up the subject of yellow jasmine, I saw the truth. In fact, it leapt to the eye."
"As always," I said coldly, "it doesn't leap to mine."
"Because you will not use your little gray cells. Who had a chance to tamper with the curry?"