Hence it has been deemed more practical to establish a kind of orthopaedic institution within the building itself in certain model schools in Rome. It consists of a costly and elaborate apparatus, to which the pupils come in turn to be suspended by the head after the method adopted in medicine to combat spinal curvature in Pott's disease (tuberculosis of the vertebral column) and rickets. Healthy children, as well as the unsound, suffer by these applications; but on the other hand, the results afford encouraging statistics. If this hanging treatment be initiated regularly at the age of six years it strikes a perfect balance with the injury caused by prolonged deterioration induced by school desks, and children are delivered from spinal disease. * * * * * =Discoveries of experimental psychology: overwork; nervous exhaustion=.--Hygiene, making its way into the school, discovered scholar's spinal curvature and scholar's myopia; experimental psychology discovered the exhaustion due to overwork, and studied the _fatigue_ of the scholar. It followed in the beaten track of medicine--that is to say, it sought to alleviate the ills it had diagnosed, and instituted a branch of science the title of which is not very clearly defined as yet, for some call it experimental psychology applied to the school, others Scientific Pedagogy. It is necessary to remember that experimental psychology was established in 1860 by Fechner, who was a physicist accustomed to experiment on _things_, not on living creatures, and who merely adapted the methods employed in physics to psychical measurements, thus founding psycho-physics. The instruments specially invented for esthesiometric measurements were of extreme precision; but the results obtained showed such variations that by mathematical law they could not be attributed to "errors of measurement," but were obviously due to "errors of method." Indeed, for the measurement of liquids it is necessary to have an instrument different from that which we use in measuring solids, although we are still in the domain of physics; we cannot measure a stuff by the quart, nor wine by the yard; how much more then must the methods of measuring physical substances and spiritual energy differ?