remember somebody speaking…the wireless voice? I was not in the library when the call came through, so I did not hear it distinctly.”
Tim recalled the mysterious voice that had spoken in the library from the aperture above the fireplace.
“Yes, sir; you told me, it was Colson—”
“I know, I know,” said the professor impatiently. “But tell me how he spoke?” His tone was almost querulous with anxiety. “I only heard the end. Was it a gruff voice, rather like mine?”
Tim shook his head.
“No, sir,” he said in surprise; “it was a very thin voice, a sort of whine…”
“A whine?” The professor almost shouted the question.
“Yes, sir.” Colson was fingering his chin with a tremulous hand.
“That is strange,” he said, speaking half to himself. “I have been trying to get him all the evening, and usually it is simple. I received his carrier wave…why should his assistant speak…? I have not heard him for three days. What did he say?”
Tim told him, as far as he could remember, the gist of the message which had come through, and for a long time the professor was silent.
‘“He does not speak English very well — the assistant, I mean — and he would find a difficulty in putting into words…you see, our language is very complicated.” And then, with a smile: “I interrupted your sleep.”
He walked slowly to the door and stood for a while, the handle in his hand, his chin on his breast.
“If anything should happen, you will find my account in the most obvious place.” He smiled faintly. “I’m afraid I am not a very good amateur mason—”
With these cryptic words he took his departure. Tim tossed from side to side and presently dropped into an uneasy doze. He dreamt that he and the professor were stalking through black, illimitable space. Around, above, below them blazed golden suns, and his ears were filled with a roar of whirling planets. Then suddenly the professor cried out in a terrible voice: “Look, look!” And there was a sharp crash of sound, and Tim sat up in bed, the perspiration streaming from every pore. Something had wakened him. In an instant he had slipped out of bed, pulled on his dressing-gown, thrust his feet into his slippers, and had raced out into the corridor. A deep silence reigned, broken only by the sound of an opening door and the tremulous voice of the butler.
“Is anything wrong, sir?”
“What did you hear?” asked Tim quickly.
“I thought I heard a shot.”
Tim waited for no more: he ran down the stairs, stumbling in the darkness, and presently came to the passage from which opened the doors of the library and the room of Planetoid 127.
The library was empty: two lights burned, accentuating the gloom. A quick glance told him that it was not here the professor was to be sought. He had no doubt that in his sleep he had heard the cry of the old man. He turned on the light in the corridor, and, trying the door of the Planetoid room, to his consternation found it was open. The room was in darkness, but again memory served him. There were four light switches near the door, and these he found. Even as he had opened the door he could detect the acrid smell of cordite, and when the light switched on he was not unprepared for the sight which met his eyes. The little machine which Colson had described as the “sound strainer” was a mass of tangled wreckage. Another instrument had been overturned; ends of cut wires dangled from roof and wall. But his eyes were for the moment concentrated upon the figure that lay beneath the open safe. It was Professor Colson, and Tim knew instinctively that the old man was dead.
Chapter IV
Colson was dead!
He had been shot at close quarters, for the hair about the wound was black and singed. Tim looked over his shoulder to the shivering butler who stood in the doorway.
“Get on the telephone to the police,” he said; and, when the man had gone, he made a brief examination of the apartment.
The destruction which the unknown murderer had wrought was hurried but thorough. Half a dozen delicate pieces of apparatus, the value and use of which Tim had no idea, had been smashed; two main wires leading from the room had been cut; but the safe had obviously been opened without violence, for the key was still in the lock. It was the shot which had wakened the boy, and he realised that the safe must have been opened subsequent to the murder.
There was no need to make an elaborate search to discover the manner in which the intruder had effected his entry: one of the heavy shutters which covered the windows had been forced open, and the casement window was ajar. Without hesitation, lightly clad as he was, Tim jumped through the window on to a garden bed. Which way had the murderer gone? Not to the high road, that was certain. There could only be one avenue of escape, and that was the path which led down to the backwater.
He considered the situation rapidly: he was unarmed, and, even if the assassin was in no better shape (which he obviously was not) he would not be a match for a powerfully built man. He vaulted up to the windowsill as the shivering butler made his reappearance.
“I’ve telephoned the police: they’re coming up at once,” he said.
“Is there a gun in the house — any kind?” said Lensman quickly.
“There’s one in the hall cupboard, sir,” replied the man, and Tim flew along the corridor, wrenched open the door, found the shotgun and, providentially, a box of cartridges. Stopping only to snatch an electric handlamp from the hall-stand, he sped into the grounds and made his way down the precipitous path which led to the river. His progress was painful, for he felt every stone and pebble through the thin soles of his slippers.
He had switched on the light of the handlamp the moment he had left the house, and here he was at an advantage over the man he followed, who was working in the dark and dared not show a light for fear of detection. That he was on the right track was not left long in doubt. Presently the boy saw something in his path, and, stooping, picked up a leather pocket-case, which, by its feel, he guessed contained money. Evidently in his hurry the murderer had dropped this.
Nearer and nearer to the river he came, and presently he heard ahead of him the sound of stumbling footsteps, and challenged his quarry.
“Halt!” he said. “Or I’ll shoot!”
The words were hardly out of his mouth when a pencil of flame quivered ahead in the darkness, something “wanged” past his head and struck the bole of a tree with a thud. Instantly Tim extinguished his lamp. The muzzle of his gun advanced, his finger on the trigger, he moved very cautiously in pursuit.
The man must be somewhere near the river now: the ground was falling more steeply. There was no sound ahead until he heard a splash of water, the hollow sound of feet striking the bottom of a boat, and a faint “chug-chug” of engines. A motor-launch! Even as he reached the riverside he saw the dark shape slipping out towards the river under cover of the trees. Raising his gun, he fired. Instantly another shot came back at him. He fired again; he might not hit the assassin, but he would at any rate alarm
