It was a nervous affection which had haunted him for years. It dated from a time when, in South America, in an acute crisis of desperate personal hazard, he had laughed the first peal of that strange laughter of which he was to be ever after afraid. Since then it had seized him many times, unexpectedly and in moments of strong excitement, to shake him like a lath. It had given him a morbid hatred of laughter in others. Recently he had thought that he was overcoming the weakness--for in two years past he had had no such seizure--and the recurrence to-night shocked and disconcerted him. He, the man of brain and attainment, to be held captive by a ridiculous hysteria, like a nerve-racked anæmic girl! The cold sweat stood on his forehead. Before long the paroxysms ceased and he grew calmer. The quiet road had merged into a busier thoroughfare. He walked on slowly till his command was regained. West of the outer moat of the Imperial Grounds, he turned up a pleasant lane-like street and presently entered his own gate. The house, into which he let himself with a latch-key, was a rambling, modern, two-story structure of yellow stucco. The lower floor was practically unused, since its tenant lived alone and did not entertain. The upper floor, besides the hall, contained a small bedroom, a bath and dressing-room and a large, barely-furnished laboratory. The latter was lined on two sides with glass-covered shelves which gave glimpses of rows of books, of steel shells, metal and crystal retorts and crucibles, the delicate paraphernalia of organic chemistry and complicated instruments whose use no one knew save himself--a fit setting for the great student, the peer of Offenbach in Munich and of Bayer in Vienna. Against the wall leaned a drafting-board, on which, pinned down by thumb-tacks, was a sketch-plan of a revolving turret. From a bracket in a corner--the single airy touch of delicacy in a chamber almost sordid in its appointments--swung a bamboo cage with a brown _hiwa_, or Japanese finch, a downy puff of feathers with its head under its wing. In the upper hall Bersonin's Japanese head-boy had been sitting at a small desk writing. Bersonin entered the laboratory, opened a safe let into a wall, and put into it something which he took from his pocket. Then he donned a dressing-gown the boy brought, and threw himself into a huge leather chair. "Make me some coffee, Ishida," he said. The servant did so silently and deftly, using a small brass _samovar_ which occupied a table of its own. With the coffee he brought his master a box of brown Havana cigars.