Indeed, recognizing the possibility that the captor might be aware, through those electrical connections, of his very ideas, he schooled his outward thoughts to complete and unquestioning submission. Yet never had his inner brain been more active, and now the immense mentality given him by the Norlaminians stood him in good stead. For every doorway, every turn, every angle and intersection of that maze of communicating passageways was being engraved indelibly upon his brain, he knew that no matter how long or how involved the way, he could retain his orientation with respect to the buried river up which they had sailed. And, although quiescent enough and submissive enough to all outward seeming, his inner brain was keyed up to its highest pitch, eager to drive Seaton's gigantic and instantaneously reacting muscles into outbursts of berserk fury at the slightest lapse of the attention of the wielder of the mastering trident. But there was no such lapse. The intelligence of the hyperman seemed to be concentrated in the glowing tips of the forceps and did not waver for an instant, even when an elevator into which he steered his charges refused to lift the immense weight put upon it. A silent colloquy ensued, then Seaton and Margaret walked endlessly up a spiral ramp. Climbed, it seemed, for hours, their feet sinking to the ankles into the resilient material of the rock-and-metal floor, while their alert guardian floated effortlessly in the air behind them, propelled and guided by his swiftly revolving tail. Eventually the ramp leveled off into a corridor. Straight ahead, two aisles--branch half right--branch half left--first turn left--third turn right--second doorway on right. They stopped. The door opened. They stepped into a large, officelike room, thronged with the peculiar, sea-horselike hypermen of this four-dimensional civilization. Everything was indescribable, incomprehensible, but there seemed to be desks, mechanisms, and tier upon tier of shelf-like receptacles intended for the storage of they knew not what. Most evident of all, however, were the huge, goggling, staring eyes of the creatures as they pressed in, closer and closer to the helplessly immobile bodies of the man and the woman. Eyes dull, expressionless, and unmoving to Earthly, three-dimensional intelligences; but organs of highly intelligible, flashing language, as well as of keen vision, to their possessors. Thus it was that the very air of the chamber was full of speech and of signs, but neither Margaret nor Seaton could see or hear them. In turn the Earthman tried, with every resource at his command of voice, thought, and pantomime, to bridge the gap--in vain. * * * * *