2721. When the sensibility mounts to the highest degree, each mass-function will then almost cease, and the organs of sense feel the weakest operation of the stimulus.
2722. Since every stimulation is a polarizing act, and each body is in polar activity towards the other at every conceivable distance, so may an extremely irritable nervous system also perceive the feeblest polarizations.
2723. The eye perceives the polarization at a remote distance from the body whence it proceeds.
2724. In hearing the vibrating body still indeed acts directly upon the ear through the vibrations of air. But a finer, i. e. more irritable ear, hears farther than one that is more dull.
2725. With an elevated sensibility the other systems also may therefore perceive the polarization of the bodies, without coming into contact with them.
2726. To perceive objects in the distance, i. e. merely their polar influence, is called Mesmerism, or animal magnetism.
2727. Now, if it is once possible for other senses besides that of sight to extend their perception into remote space, it no longer matters as to the magnitude of the latter. A feebly charged electrical machine only attracts bodies that are near, one strongly loaded, those which are more remote; such is the case too with weak and strong magnets.
2728. The integument at once perceives electrified surfaces at certain distances; now, as every surface appears electric to the integument, so must the latter, if its sensibility is very much elevated, perceive something of that sort in every proportionate distance.
2729. But homologous polarities only act upon each other, and therefore traverse thoroughly through heterologous bodies. Thus the magnet attracts the iron filings through the table-board, unhindered by the interposed wood, and without any regard being paid to this, or its being even perceived.
2730. The senses may therefore perceive their homologous polarities through other bodies, walls, and such like. By virtue of their perception, they stand in relation to them.