The boy used not to knock at the glass door: he scratched; and as Anthime remained bending over his table without answering, he would step forward three or four paces and in his fresh voice fling out a “_Permesso?_” which filled the room with azure. From his voice one would have taken him for an angel; in reality he was an under-executioner. What new victim was he bringing in the bag which he dropped on to the torture table? Anthime was often too much absorbed to open the bag at once; he threw a hasty glance at it; if he saw it stirring, he was satisfied: rats, mice, sparrows, frogs--all were welcome to this Moloch. Sometimes Beppo brought him nothing; but he came in all the same. He knew that Armand-Dubois was expecting him even empty-handed; and while the boy, standing silent beside the man of science, leaned forward to watch some abominable experiment, I wish I could certify that the man of science experienced no thrill of pleasure--no false god’s vanity--at feeling the child’s astonished look fall, in turn, with terror upon the animal, and with admiration upon himself. Anthime’s modest pretension, before going on to deal with human beings, was merely to reduce all the animal activities he had under observation, to what he termed “tropisms.” Tropisms! The word was no sooner invented than nothing else was to be heard of; an entire category of psychologists would admit nothing in the world but tropisms. Tropisms! A sudden flood of light emanated from these syllables! Organic matter was obviously governed by the same involuntary impulses as those which turn the flower of the heliotrope to face the sun (a fact which is easily to be explained by a few simple laws of physics and thermochemistry). The order of the universe could at last be hailed as reassuringly benign. In all the motions of life, however surprising, a perfect obedience to the agent could be universally recognised. With the purpose of wringing from the helpless animal the acknowledgment of its own simplicity, Anthime Armand-Dubois had just invented a complicated system of boxes--boxes with passages, boxes with trap-doors, boxes with labyrinths, boxes with compartments (some with food in them, some with nothing, some sprinkled with a sternutatory powder), boxes with doors of different shapes and colours--diabolical instruments, which a little later became the rage in Germany under the name of _Vexierkasten_, and were of the greatest use in helping the new school of psycho-physiologists to take another step forward in the path of unbelief. And in order to act severally on one or other of the animal’s senses, on one or other portion of its brain, he blinded some, deafened others, emasculated, skinned or brained them, depriving them of one organ after another, which you would have sworn indispensable, but which the animal, for Anthime’s better instruction, did without.