"I can't tell you . . . but you mustn't go!"
Simon looked straight at her.
"Betty," he said, "as I've told you before, you're heading for trouble. I've heard of real tough women who looked like angels, but I've never really believed in them. If you're that sort, I'll eat the helmet off every policeman in London. I don't know why you're in this, but even if you are as free as you say, you don't seem to be enjoying it. I'm giving you a chance. Tell me everything you know, help me all you can, and when the crash comes I'll guarantee to see you through it. You can take that as official."
She moved her head wearily.
"It's useless."
"You mean Raxel's got some sort of hold over you?"
"If you like."
"What is it?"
"I can't tell you," she said hopelessly.
The Saint's mouth tightened.
"Very well," he said. "On your own head be it. But remember my offer--it stays open till the very last moment."
He rose, and found her hand clutching his wrist.
"Where are you going?" she asked frightenedly.
"To unlock that door, and find out what's in this mysterious room," said the Saint, a trifle grimly. "I Ji^think I told you that before,"
"You can't. These locks are easy, but there's a special lock on that door."
"And right next door is an empty room, and there's nobody else but myself on that side of the house. Also, there's plenty of ivy, and it looks pretty strong to me. I don't think the window will keep me waiting outside for long,"
He disengaged her hand, and stepped away a little so that she could not grab him again.
"I'll lock your door when I go out," he said.
He went out, and she had not tried to call him back. It was the work of a few moments only to relock the door from the outside, and then he stole across the corridor to the door of the room which he had marked down because of its window, which was separated by no more than a couple of yards from the window of the locked room.
The ivy, as he had guessed, was strong; and as he had said, there was no one but himself sleeping on that side of the house, so that the noise he made was of no consequence. Better still, the Professor, when fitting the special lock to the door of the mystery room, had clearly overlooked the possibilities that the ivy-covered walls presented to an active young man, and the catch of the window was not even secured.
Simon slid up the sash cautiously and slithered over the sill. Then he switched on his torch, and his jaw dropped.
The centre of the room was occupied by a rough wooden bench, and on this was set up a complicated arrangement of retorts, condensers, aspirators, and burners. They seemed to form a connected chain, as if they were intended for the distillation of some subtle chemical substance which was submitted to various processes of blending and refinement during the course of its passage through the length of the apparatus. The chain terminated in a heavy cylinder such as oxygen is supplied in.
Simon studied the arrangement attentively; but he was no chemist, and he could make nothing of it. In his cautious way, he decided not to touch any of the components, for he appreciated that any chemical process which had to be surrounded with so much secrecy might possibly be pregnant with considerable danger for the ignorant meddler, and the association of Bernhard Raxel with the mystery would not have encouraged anyone to imagine that all those elaborate precautions had been taken to protect the secret of the manufacture of some new kind of parlour fireworks to amuse the children. But the Saint did take the liberty of peering closely at the apparatus, and the result was somewhat startling--so startling that it was some time before he was in a condition to pass on to the examination of the rest of the room.
On another bench, against one wall, was a row of glass bottles, unlabelled, containing an assortment of crystals, powders, and liquids, none of which had an appearance with which the Saint was familiar.
This, then, was the secret. A comprehensive tour revealed nothing more, and Simon, his objective accomplished, prepared to go. He lighted a cigarette and hesitated over his departure for a few moments, but he could think of nothing that a longer stay might achieve, and presently he accepted the inevitable with a shrug. Yet that delay had certain consequences--he was so absorbed with his problem that he did not visualize those consequences that night.
He returned to his own room as stealthily as he had left it, but the house remained shrouded in unbroken silence. The Saint's careful and expert examination had revealed a neat and inconspicuous burglar alarm attached to the door of the locked room. This, he had divined immediately, worked a buzzer under Raxel's own pillow, and therefore Raxel would have no fear that the Saint would be able to make an attempt to discover his secret without automatically calling the attention of the whole house to his nocturnal prowling. In which comfortable belief Professor Bernhard Raxel was beautifully and completely wrong.
Simon climbed into bed, and for the first time in his life failed to fall asleep immediately. He wanted to know what sinister secret lay behind the mysterious laboratory in that house, and most of all he wanted to know why Betty Tregarth should spend most of her time there. Betty Tregarth wasn't likely to be a willing associate of a man like the Professor --he was ready to swear to that. Was it possible that she had some special knowledge of chemistry, and had been blackmailed or coerced into assisting the Professor? . . . And then Simon Templar suddenly remembered the curious feeling that had come over him when he was peering at the apparatus in the locked room, and gasped aloud in a blinding blaze of understanding.
He was up early next morning, and the first thing he did was to go down to the village post office. He got a call through to London, to a friend who could help to answer some of the questions that were bubbling through his brain. And what he heard fascinated him.
It was on his way back to the Beacon that he suddenly recalled a detail of his delay the previous night, and therefore the immediate development failed to surprise him.
He had just finished breakfast when Raxel, Marring, and Crantor entered the dining room, and Simon saw at once from their bearing that they had already made an interesting discovery. Raxel came straight over to his table and the other two followed.
'' Good-morning,'' said the Saint, in his cheerful way.
"Good-morning, Mr. Smith," said the Professor. "I am sorry to hear that you walk in your sleep."
Simon looked blank.
"So am I," he said. "Do I?"
"I think so," said the Professor, and an automatic pistol showed in his hand. "Please put your hands up, Mr. Smith--I have just seen your cigarette ash on the floor of the laboratory."
Simon rose, yawning, with his arms raised.
"Anything to oblige," he murmured. "Have you put it under the microscope and discovered the brand of tobacco?"
"That is not what is puzzling me just now," said the Professor blandly. "Search him, Marring. We have already ransacked your room, Mr. Smith, and the letter which I was expecting to find was not there, so that if you have written it, it is likely to be on your person."
Simon submitted to the search without protest, and smiled at the look of savagely restrained consternation that broke momentarily through Raxel's mask of suavity when the search proved fruitless.
"Rather jumping to conclusions, weren't you?" the Saint suggested mildly.
Basher Tope stood in the doorway.
"I saw him go out before breakfast," said Tope clamorously. "He went down to the village. He must have used the telephone."