Sherman grabbed, but this only fixed the ape-man in his evident opinion that the object he held was of value. He gripped it all the tighter, turned an amiable face toward Sherman and gibbered. Losing patience at this unfortunate contretemps when time was so precious, the aviator lifted an iron foot and kicked him, vigorously and with purpose, in the place where kicks do the most good. The ape-man pitched forward, dropping the fascinating pin, then rose and came toward Sherman, his expression clearly indicating his intention of tearing the American limb from limb. The cage was narrow: the ape-man the bigger of the two. Sherman thought hard and fast. The oil-ball! He leaped for the lectern, snatched it open, seized the ape-man's oil-ball and held it aloft as though to throw it out into the corridor. With a wail of anguish the simian clutched at the precious object. Sherman squeezed it enough to let a little stream run forth, holding it just out of his reach, and as he stabbed for it again, tossed it back into a corner of the cell. The ape-man leaped upon it covetously, and Sherman bent over the bars, fumbling in his nervous haste to unlock them. Luckily the safety-pin fitted. With a subdued click the bars swung inward and he was out in the corridor. Another moment and Gloria was free also. "Any more people in here?" Sherman called. Three voices answered and he hurried from cage to cage, setting them free as the warning blue lights that prohibited shouting began to flicker around the roof. "Come on," he called, "we must get out of here, quick!" They hesitated a moment between the two doors, chose that at the upper end. As they raced through it, they heard a panel clash somewhere. The Lassans were investigating. They were in one of the passages through which the cars ran, with alternate bars of light and dark across it marking the termination of side-passages. "Look!" said Gloria. Into the cage-room they had just quitted a car was coming, its featureless front gliding noiselessly along the track. "In here," said Sherman, pulling the others after him down the nearest lighted passage. Followed by the other four Sherman followed it steadily along to the right, where it ended at a door. "What now?" said someone. "In," decided Gloria. "Likely to be a cage-room as not." Sherman searched for the inevitable finger-holes, found them and pressed. The door swung back on-- A Lassan reclining at ease on one of the curious twisted benches beside which stood a tall jar of the same yellow-flecked green material they had seen the others devouring. The room was blue-domed but very small, and its walls were covered with soft green hangings in pendulous drops. A thought-helmet was on the elephant-man's head; its other end was worn by one of the mechanical people whose back was to the door as they entered, and who appeared to be working some kind of machine that punched little holes of varying shape in a strip of bright metal.