Dusk found Nayland Smith and me at the top bedroom window. We knew, now that poor Forsyth's body had been properly examined, that he had died from poisoning. Smith, declaring that I did not deserve his confidence, had refused to confide in me his theory of the origin of the peculiar marks upon the body.  
"On the soft ground under the trees," he said, "I found his tracks right up to the point where—something happened. There were no other fresh tracks for several yards around. He was attacked as he stood close to the trunk of one of the elms. Six or seven feet away I found some other tracks, very much like this."
 
He marked a series of dots upon the blotting-pad, for this conversation took place during the afternoon.
 
"Claws!" I cried. "That eerie call! like the call of a nighthawk—is it some unknown species of—flying thing?"
 
"We shall see, shortly; possibly to-night," was his reply. "Since, probably owing to the absence of any moon, a mistake was made"—his jaw hardened at the thought of poor Forsyth—"another attempt along the same lines will almost certainly follow—you know Fu-Manchu's system?"
 
So in the darkness, expectant, we sat watching the group of nine elms. To-night the moon was come, raising her Aladdin's lamp up to the star world and summoning magic shadows into being. By midnight the high-road showed deserted, the common was a place of mystery; and save for the periodical passage of an electric car, in blazing modernity, this was a fit enough stage for an eerie drama.
[52]
 
No notice of the tragedy had appeared in print; Nayland Smith was vested with powers to silence the Press. No detectives, no special constables, were posted. My friend was of opinion that the publicity which had been given to the deeds of Dr. Fu-Manchu in the past, together with the sometimes clumsy co-operation of the police, had contributed not a little to the Chinaman's success.
 
"There is only one thing to fear," he jerked suddenly; "he may not be ready for another attempt to-night."
 
"Why?"
 
"Since he has only been in England for a short time, his menagerie of venomous things may be a limited one at present."
 
Earlier in the evening there had been a brief but violent thunderstorm, with a tropical downpour of rain, and now clouds were scudding across the blue of the sky. Through a temporary rift in the veiling the crescent of the moon looked down upon us. It had a greenish tint, and it set me thinking of the filmed, green eyes of Fu-Manchu.
 
The cloud passed and a lake of silver spread out to the edge of the coppice; where it terminated at a shadow bank.
 
"There it is, Petrie!" hissed Nayland Smith.
 
A lambent light was born in the darkness; it rose slowly, unsteadily, to a great height, and died.
 
"It's under the trees, Smith!"
 
But he was already making for the door. Over his shoulder:
 
"Bring the pistol, Petrie!" he cried; "I have another. Give me at least twenty yards' start or no attempt may be made. But the instant I'm under the trees, join me."
 
Out of the house we ran, and over on to the common, which latterly had been a pageant-ground for phantom warring. The light did not appear again; and as Smith plunged off toward the trees, I wondered if he
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knew what uncanny thing was hidden there. I more than suspected that he had solved the mystery.
 
His instructions to keep well in the rear I understood. Fu-Manchu, or the creature of Fu-Manchu, would attempt nothing in the presence of a witness. But we knew full well that the instrument of death which was hidden in the elm coppice could do its ghastly work and leave no clue, could slay and vanish. For had not Forsyth come to a dreadful end while Smith and I were within twenty yards of him?
 
Not a breeze stirred, as Smith, ahead of me—for I had slowed my pace—came up level with the first tree. The moon sailed clear of the straggling cloud wisps which alone told of the recent storm; and I noted that an irregular patch of light lay silvern on the moist ground under the elms where otherwise lay shadow.
 
He passed on, slowly. I began to run again. Black against the silvern patch, I saw him emerge—and look up.
 
"Be careful, Smith!" I cried—and I was racing under the trees to join him.
 
Uttering a loud cry, he leaped—away from the pool of light.
 
"Stand back, Petrie!" he screamed. "Back! farther!"
 
He charged into me, shoulder lowered, and sent me reeling!
 
Mixed up with his excited cry I had heard a loud splintering and sweeping of branches overhead; and now as we staggered into the shadows it seemed that one of the elms was reaching down to touch us! So, at least, the phenomenon presented itself to my mind in that fleeting moment while Smith, uttering his warning cry, was hurling me back.
 
Then the truth became apparent.
 
With an appalling crash, a huge bough fell from above. One piercing awful shriek there was, a
[54]
crackling of broken branches, and a choking groan....
 
The crack of Smith's pistol close beside me completed my confusion of mind.
 
"Missed!" he yelled. "Shoot it, Petrie! On your left! For God's sake don't miss it!"
 
I turned. A lithe black shape was streaking past me. I fired—once—twice. Another frightful cry made yet more hideous the nocturne.
 
Nayland Smith was directing the ray of a pocket torch upon the fallen bough.
 
"Have you killed it, Petrie?" he cried.
 
"Yes, yes!"
 
I stood beside him, looking down. From the tangle of leaves and twigs an evil yellow face looked up at us. The features were contorted with agony, but the malignant eyes, wherein light was dying, regarded us with inflexible hatred. The man was pinned beneath the heavy bough; his back was broken; and, as we watched, he expired, frothing slightly at the mouth, and quitted his tenement of clay leaving those glassy eyes set hideously upon us.
 
"The pagan gods fight upon our side," said Smith strangely. "Elms have a dangerous habit of shedding boughs in still weather—particularly after a storm. Pan, god of the woods, with this one has performed Justice's work of retribution."
 
"I don't understand. Where was this man—?"
 
"Up the tree, lying along the bough which fell, Petrie! That is why he left no footmarks. Last night no doubt he made his escape by swinging from bough to bough, ape-fashion, and descending to the ground somewhere at the other side of the coppice."
 
He glanced at me.
 
"You are wondering, perhaps," he suggested, "what caused the mysterious light? I could have told you this morning, but I fear I was in a bad temper, Petrie. It's very simple; a length of tape soaked in spirit or something of the kind, and shel
[55]
tered from the view of any one watching from your windows, behind the trunk of the tree; then, the end ignited, lowered, still behind the tree, to the ground. The operator swinging it around, the flame ascended, of course. I found the unburned fragment of the tape used last night, a few yards from here."
 
I was peering down at Fu-Manchu's servant, the hideous yellow man who lay dead in a bower of elm leaves.
 
"He has some kind of leather bag beside him," I began.
 
"Exactly!" rapped Smith. "In that he carried his dangerous instrument of death; from that he released it!"
 
"Released what?"
 
"What your fascinating friend came to recapture this morning."
 
"Don't taunt me, Smith!" I said bitterly. "Is it some species of bird?"
 
"You saw the marks on Forsyth's body, and I told you of those which I had traced upon the ground here. They were caused by claws, Petrie!"
 
"Claws! I thought so! But what claws?"
 
"The claws of a poisonous thing. I recaptured the one used last night, killed it—against my will—and buried it on the mound. I was afraid to throw it in the pond, lest some juvenile fisherman should pull it out and sustain a scratch. I don't know how long the claws would remain venomous."
 
"You are treating me like a child, Smith," I said, slowly. "No doubt I am hopelessly obtuse, but perhaps you will tell me what this Chinaman carried in a leather bag and released upon Forsyth. It was something which you recaptured, apparently with the aid of a plate of cold turbot and a jug of milk. It was something, also, which Kâramanèh had been sent to recapture with the aid—"
 
I stopped.
 
"Go on," said Nayland Smith, turning the ray
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to the left; "what did she have in the basket?"
 
"Valerian," I replied mechanically.
 
The ray rested upon the lithe creature that I had shot down.
 
It was a black cat!
 
"A cat will go through fire and water for valerian," said Smith; "but I got first innings this morning with fish and milk! I had recognized the imprints under the trees for those of a cat, and I knew that if a cat had been released here it would still be hiding in the neighbourhood, probably in the bushes. I finally located a cat, sure enough, and came for bait! I laid my trap, for the animal was too frightened to be approachable, and then shot it; I had to. That yellow fiend used the light as a decoy. The branch which killed him jutted out over the path at a spot where an opening in the foliage above allowed some moon rays to penetrate. Directly the victim stood beneath, the Chinaman uttered his bird-cry; the one below looked up, and the cat, previously held silent and helpless in the leather sack, was dropped accurately upon his head!"
 
"But—" I was growing confused.
 
Smith stooped lower.
 
"The cat's claws are sheathed now," he said; "but if you could examine them you would find that they are coated with a shining black substance. Only Fu-Manchu knows what that substance is, Petrie; but you and I know what it can do!"