George Lacklander said in an unrecognizable voice, “All this conjecture!”
“No,” Alleyn said, “I assure you. Not conjecture.” He looked at Lady Lacklander and Mark. “Shall I go on?”
Lady Lacklander, using strange unco-ordinated gestures, fiddled with the brooches that, as usual, were stuck about her bosom. “Yes,” she said, “go on.”
Mark, who throughout Alleyn’s discourse had kept his gaze fixed on his father, said, “Go on. By all means. Why not?”
“Right,” Alleyn said. “Now the murderer was faced with evidence of identity. One imagines the trout glistening with a clear spiked heel-mark showing on its hide. It wouldn’t do to throw it into the stream or the willow grove and run away. There lay the Colonel with his hands smelling of fish and pieces of cut grass all round him. For all his murderer knew, there might have been a witness to the catch. This, of course, wouldn’t matter as long as the murderer’s identity was unsuspected. But there is a panic sequel to most crimes of violence, and it is under its pressure that the fatal touch of over-cleverness usually appears. I believe that while the killer stood there, fighting down terror, the memory of the Old ’Un, lying on Bottom Bridge, arose. Hadn’t Danberry Phinn and the Colonel quarrelled loudly, repeatedly and vociferously — quarrelled that very afternoon — over the Old ’Un? Why not replace the Colonel’s catch with the fruits of Mr. Phinn’s poaching tactics and drag, not a red-herring, but a whacking great trout across the trail? Would that not draw attention towards the known enemy and away from the secret one? So there was a final trip in the punt. The Colonel’s trout was removed and the Old ’Un substituted. It was at this juncture that Fate, in the person of Mrs. Thomasina Twitchett, appeared to come to the murderer’s aid.”
“For God’s sake,” George Lacklander shouted, “stop talking—” He half formed an extremely raw epithet, broke off and muttered something indistinguishable.
“Who are you talking about, Rory?” Lady Lacklander demanded. “Mrs. who?”
“Mr. Phinn’s cat. You will remember, Mrs. Cartarette told us that in Bottom Meadow she came upon a cat with a half-eaten trout. We have found the remains. There is a triangular gash corresponding with the triangular flap of skin torn off by the sharp stone, and as if justice or nemesis or somebody had assuaged the cat’s appetite at the crucial moment, there is also a shred of skin bearing the unmistakable mark of part of a heel and the scar of a spike.”
“But can all this—” Mark began. “I mean, when you talk of correspondence—”
“Our case,” Alleyn said, “will, I assure you, rest upon scientific evidence of an unusually precise character. At the moment, I’m giving you the sequence of events. The Colonel’s trout was bestowed upon the cat. Lady Lacklander’s paint-rag was used to clean the spike of the shooting-stick and the murderer’s hands. You may remember, Dr. Lacklander, that your grandmother said she had put all her painting gear tidily away, but you, on the contrary, said you found the rag caught up in a briar bush.”
“You suggest then,” Mark said evenly, “that the murder was done some time between ten to eight, when my grandmother went home, and a quarter past eight, when I went home.” He thought for a moment and then said, “I suppose that’s quite possible. The murderer might have heard or caught sight of me, thrown down the rag in a panic and taken to the nearest cover only to emerge after I’d picked up the sketching gear and gone on my way.”
Lady Lacklander said after a long pause, “I find that a horrible suggestion. Horrible.”
“I daresay,” Alleyn agreed dryly. “It was an abominable business, after all.”
“You spoke of scientific evidence,” Mark said.
Alleyn explained about the essential dissimilarities in individual fish scales. “It’s all in Colonel Cartarette’s book,” he said and looked at George Lacklander. “You had forgotten that perhaps.”
“Matter of fact, I — ah — I don’t know that I ever read poor old Maurice’s little book.”
“It seems to me to be both charming,” Alleyn said, “and instructive. In respect of the scales it is perfectly accurate. A trout’s scales, the Colonel tells us, are his diary in which his whole life-history is recorded for those who can read them. Only if two fish have identical histories will their scales correspond. Our two sets of scales, luckily, are widely dissimilar. There is Group A, the scales of a nine- or ten-year-old fish who has lived all his life in one environment. And there is group B, belonging to a smaller fish who, after a slow growth of four years, changed his environment, adopted possibly a sea-going habit, made a sudden spurt of growth and was very likely a newcomer to the Chyne. You will see where this leads us, of course?”
“I’m damned if I do,” George Lacklander said.
“O, but yes, surely. The people who, on their own and other evidence, are known to have handled one fish or the other are Mr. Phinn, Mrs. Cartarette and the Colonel himself. Mr. Phinn caught the Old ’Un; Mrs. Cartarette tells us she tried to take a fish away from Thomasina Twitchett. The Colonel handled his own catch and refused to touch the Old ’Un. Lady Lacklander’s paint-rag with the traces of both types of fish scales tells us that somebody, we believe the murderer, handled both fish. The further discovery of minute blood-stains tells us that the spike of the shooting-stick was twisted in the rag after being partially cleaned in the earth. If, therefore, with the help of the microscope we could find scales from both fish on the garments of any one of you, that one would be Colonel Cartarette’s murderer. That,” Alleyn said, “was our belief.”
“Was?” Mark said quickly, and Fox, who had been staring at a facetious Victorian hunting print, re-focussed his gaze on his senior officer.
“Yes,” Alleyn said. “The telephone conversation I have just had was with one of the Home Office men who are looking after the pathological side. It is from him that I got all this expert’s stuff about scales. He tells me that on none of the garments submitted are there scales of both types.”
The normal purplish colour flooded back into George Lacklander’s face. “I said from the beginning,” he shouted, “it was some tramp. Though why the devil you had to — to—” he seemed to hunt for a moderate word—“to put us through the hoops like this—” His voice faded. Alleyn had lifted his hand. “Well?” Lacklander cried out. “What is it? What the hell is it? I beg your pardon, Mama.”
Lady Lacklander said automatically, “Don’t be an ass, George.”