'For a memorial,' replied lord Herbert, 'of the folly of the man who placeth his hopes in man. That wonderful engine; it is now nearly three years since I showed it to his blessed majesty in the Tower of London, also with him to the dukes of Richmond and Hamilton, and two extraordinary ambassadors besides, but of them all no man hath ever sought to look upon it again. It is a form of the Proteus-like perpetuum mobile--a most incredible thing if not seen.' He then proceeded to show her how, as every spoke passed the highest point, the weight attached to it immediately hung a foot farther from the centre of the wheel, and as every spoke passed the lowest point, its weight returned a foot nearer to the centre, thus causing the leverage to be greater always on one and the same side of the wheel. Few of my readers will regret so much as myself that I am unable to give them the constructive explanation his lordship gave Dorothy as to the shifting of the weights. Whether she understood it or not, I cannot tell either, but that is of less consequence. Before she left the workshop that morning, she had learned that a thousand knowledges are needed to build up the pyramid on whose top alone will the bird of knowledge lay her new egg. When he had finished his explanation, lord Herbert returned to his work, leaving Dorothy again to her own observations. And now she would gladly have questioned him about the huge mass of brick and iron, which, now standing silent, cold, and motionless as death, had that night seemed alive with the fierce energy of flame, and yet sorely driven, sighing, and groaning, and furiously hissing; but as it was not now at work, she thought it would be better to wait an opportunity when it should be in the agony of its wrestle with whatever unseen enemy it coped withal. She did not know that, the first of its race, it was not quite equal to the task the magician had imposed upon it, but that its descendants would at length become capable of doing a thousand times as much, with the swinging joy of conscious might, with the pant of the giant, not the groan of the overtasked stripling urging his last effort. She was standing by a chest, examining the strangely elaborate and mysterious-looking scutcheon of its lock, when his lordship's hammering ceased, and presently she found that he was by her side.