He seated himself beside her on the couch and lit a cigarette.

"There is no time for full details, dear lady. Be satisfied with these.

First, I sailed this afternoon from London--by deputy, you understand.

To-night I shall travel a certain distance south by car, afterwards by rail. At a certain port, a Mr. So-and-So will board and occupy his reserved cabin on a swift steamer bound for Madeira. At Madeira Mr.

So-and-So and Mr. Deputy will meet--just meet and no more. Then Mr.

Deputy will disappear as such, Mr. So-and-So will disappear as such, and Mr. Bullard will continue his journey to Cape Town."

"Oh, you are horribly clever! ... Your deputy is like you in appearance?"

"Very; and as I've had occasion to use him before, he knows my little ways.... But now, Mrs. Lancaster, I must ask you to get busy." He rose, took the box from the mantel and extracted the sphere. "Don't be afraid,"

he said, as she rose, also, with a shiver. "Only be careful." He laid it in her hand.

"Will it hurt much?" she whispered.

"No--not much. Disagreeable of course, but not deadly."

"You're sure it won't--kill?"

"I give you my word. Now, please,--at once." He went over to the door and unlocked it. "Come!"

She joined him. "Oh, yes, I know exactly what to do," she said, answering a question.

"Very well." He returned to the hearth. "Now I'm going to ring for Mr.

Caw.... There!"

She opened the door and slipped out. At the rail directly over the foot of the stair she took her stand.

Ere long she heard a door in the distance open and shut. Then she heard Caw coming along the pa.s.sage leading from the kitchen premises....

As Caw placed his foot on the first step, something bright flashed down within a yard of his eyes and burst on the stair with a slight report.

When Bullard looked over, a moment later, he nodded and said: "That's all right. He won't stir for fifteen minutes, anyway, and I hope I shan't need five."

It then appeared necessary to conduct Mrs. Lancaster back to her room and administer to her what remained in the tiny gold flask.

CHAPTER XXVIII

"Curse that green stuff!" said Bullard under his breath. "I'd sooner handle a bunch of live wires."

He was standing in front of the clock, in the glow of an overhanging lamp, the only one he had switched on on entering the firelit room.

The pendulum in its callous swing fairly blazed. There was no sound save a half-stifled, irritating ticking.

Bullard presented rather a curious, if not uncanny, spectacle then. His countenance was covered by a gla.s.s mask such as the chemist dons while preparing or studying some highly unstable and dangerous substance. Even more than death he feared pain and disfigurement. His method of dealing with Christopher's clock had been carefully thought out. In the rainproof coat which he wore was a respirator, oxygenated, as well as sundry little tools. For it was the green fluid that had engaged his wits most seriously: it must be got rid of; its powers, whatever they were, dispersed, before he dared tackle the clock itself; and the dispersal must be effected from the greatest distance possible.

Well, he had conceived a way which promised but moderate risk to his own person. Having finished his brief outward examination of the clock, he produced a disk of white paper, an inch and a half in diameter, gummed on one side. Raising the mask slightly, he moistened the disk, and applied it to the clock's case, almost at the bottom of the reservoir. Against the green background the mark showed very distinctly. For a moment or two he regarded it critically, then went to the door and turned the key. He stepped briskly up the room, halting at the heavy brown curtains drawn across the bay-window.

From inside his coat he brought a gleaming weapon with a long barrel and an unusually large b.u.t.t--an air pistol of great power and reliability. In the old South African times Bullard had been a notable shot with rifle and revolver, and practice during the last few days had shown him that his hand and eye still retained a good deal of their cunning. Moreover, it was an easy mark he had before him now. The chief risk lay in an extremely violent explosion of the green fluid, but he hardly believed in such a result. Christopher was sure to have thought of something more subtle than mere widespread destruction, which might involve friends, not to mention property, no less than enemies. Something that burned, something that asphyxiated--something undoubtedly cruel and treacherous and horrible--existed in that green fluid; but when its time came, it would attack its victim with little sound, if not in absolute silence. So Bullard had imagined it, though he was prepared to find himself wrong.

The pistol was already loaded, its charge of compressed air awaiting but the touch of release. Bullard undid the safety-catch, took a glance round, and pa.s.sed between the curtains, re-drawing them till they almost touched. With his left hand he grasped the edges at a level with his chin, leaving a narrow aperture above that level through which he could aim. If an explosion did take place, he was fairly secure from flying fragments; if the atmosphere became too perilous, the window was at hand.

He raised the weapon to the aperture and protruded the barrel. An easy shot, indeed! He would soon know what ... d.a.m.n! what was that? Footsteps on the gravel beneath the window? Withdrawing the pistol, he moved to the window and listened. The fastenings of the mask enc.u.mbered his hearing; he could not be sure. But, next moment, peering through the misty pane on the right he saw a man's figure, too small for either Craig or France, move from the steps into the ruddily lighted doorway. And far away, as it seemed, an electric bell purred.

Wrath at the interruption rather than fear of discovery and capture possessed Bullard. Caw was helpless for the present, and it was not the old housekeeper's business to answer the bell. The visitor would have to wait awhile. Anyway, there was plenty of time for escape.... But was he going to flee empty-handed, leaving that cursed clock unexplored?

He turned quickly back to the curtains, and again protruded the pistol--and all but dropped it.

Between him and the clock a girl was standing--a girl in an apple-green evening frock. She had nut-brown hair and a beautiful neck, and she was inclined to plumpness. Apparently she was watching the pendulum. Soon, however, she moved and looked around her. There was a slight flush on the delicate tan of her cheeks, and she smiled faintly as at some foolish thought. Then, glancing at something in her hand, she shook her head while a tiny frown superseded the smile.

She stepped to the door and turned the handle--and gave a little gasp.

Bullard saw her colour go out, saw her shoulder seek the support of the door. In that instant he might have over-awed her, stunned her with alarm, but in the next she straightened up and did an unexpected thing.

She drew the key from the locked door and walked deliberately to the writing table. For a moment she seemed to require the support of its ledge, yet steadily enough she pa.s.sed back to the clock.

There she wheeled about. Up went her right hand holding a little revolver. She spoke softly, not unwaveringly, but quite clearly.

"Whoever you are, I think you had better come out. They will be here immediately. I've rung for them. You can't escape!"

There was no response. Bullard was thinking hard. Ought he to overpower her or risk the long drop from the window?

"I will count three," she said, "and if you don't come out, I will shoot!

One ... two ... th--"

"Do not forget," said a m.u.f.fled voice, "that I can shoot also."

"You horrid pig!" she cried. "Take that!" Crack went the revolver--crash went the bulb and shade above the writing-table.

Bullard stepped forth. There was a greyish shade on his face, but his lips smiled stiffly behind the gla.s.s mask.

"Stand away from the clock, and be good enough to return the key to the door," he said.

The sight of him daunted her, yet not for long. She fired again--blindly, one may suppose. The bullet pa.s.sed over his head, between the curtains, and through the window. A sound of vigorous knocking came from below.

"You little devil!" snarled Bullard, and ran at her.

Then her nerve weakened and she darted toward the door of the pa.s.sage.

Ere she could reach it, it flew open, and, dropping the revolver, she fell into the arms of the panting Alan.

"Good G.o.d! what's this?" he cried at the extraordinary appearance of Bullard and the smoke wreaths in the atmosphere. "Are you all right?" he whispered to the girl.

Teddy dashed in, gave a shout and made for Bullard, only to be brought up short by a shining muzzle almost in his face.

From downstairs a female voice rose in shrieks; from the stairs came a man's, shouting in a foreign tongue. Next moment there fell a frantic beating on the door.

Marjorie darted from her refuge, thrust home the key and turned it.