"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 glass 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 butt—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 passed 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 … Damn! 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 encumbered 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.