"And you couldn't be blamed," admitted Clason readily. "This toy of a model is hardly convincing. But come along with me and I'll show you how the Liberator looks in actual operation." * * * * * The office rug concealed a trap door which gave upon a spiral stair. Below, Clason unlocked another door and led the way through a narrow and tremendously long passage lighted at intervals by small electric bulbs. Presently another door yielded to the inventor's deft touch and closed behind them with a portentous chug. Here the darkness was so utter and intense that Quest imagined he could feel the weight of it on his shoulders. From the slope of the passageway and the muffled beat of machinery that had come to his ears on the way along, he guessed that he was below ground in some chamber at the rear of the factory. He gave a low exclamation as Clason switched on the toplight. No wonder the darkness had seemed of almost supernatural quality! Even the hard white glare of the daylight arc was grisly. Its rays rebounded from the liquids of the great circular tank in a blinding dazzle of color, while the dull black walls and ceiling were so perfectly absorptive that beyond arm's length they became to all effects invisible. Even the ledge on which he stood--the shoulder of the vat--gave Quest the feeling that to move would be to step off into a bottomless pit. But Clason took his attention at once, pointing here and there in his quick, nervous way to indicate how faithfully the Liberator had been reproduced from the model. In all respects the arrangements were the same, with the addition that here a long plank like a spring-board extended out from a wall-mount as far as the central compartment of the tank, and that from its end a narrow ladder hung down to the surface of the Chartreuse liquid. A double-throw switch fixed to the wall above the base of the plank was evidently the source of electrolytic control. "When you throw the switch to plus," said Clason, pointing to the chalk-marked sign above, "you produce the violent electrolytic action needed to bring about a liberation. All the rest of the time it should be closed at minus, in order to maintain the anti-action which I explained to you. "Now let's rehearse, so that when the time for the real performance arrives we can be sure of running it off without a hitch." "All right, sir," nodded Quest, so dazed by the glittering light that he was hardly conscious of what he said. * * * * * "First," said Clason, running lightly up the steps to the plank, "you walk out to the end, like this, and start down the ladder. Then you lower yourself into the tank. The liquid is at body temperature; it's neither strongly acid nor caustic; it will cause you no injury or discomfort whatever.