Our present view is that the act of magnetisation consists in a re-arrangement and co-ordination of previously existing magnetic elements, lying dormant, so to speak, in iron and other magnetic materials; only a very small fraction of the whole number being usually brought into activity at any one time, and not necessarily always the same actual set. Only a small and indiscriminate selection is made from all the molecular loops; and it can be a different group each time, or some elements may be different and some the same, whenever a fresh individual or magnet is brought into being. All this can be said concerning the old process of magnetisation—the process as it was doubtless familiar to the unknown discoverer of the lodestone, to the ancient users of the mariner's compass, and to Dr Gilbert of Colchester, the discoverer of the magnetised condition of the Earth. But within the nineteenth century a fresh process of magnetisation has been discovered, and this new or electrical process is no longer obviously dependent on the existence of antecedent magnetism, but seems at first sight to be a property freshly or spontaneously generated, as it were. The process was discovered as the result of setting electricity into motion. So long as electricity was studied in its condition at rest on charged conductors, as in the old science of electrostatics or frictional electricity, it possessed no magnetic properties whatever, nor did it encroach on the magnetic domain: only vague similarities in the phenomena of attraction and repulsion aroused attention. But directly electricity was set in motion, constituting what is called an electric current, magnetic lines of force instantly sprang into being, without the presence of any steel or iron; and in twenty years they were recognised. These electrically generated lines of force are similar to those previously known, but they need no matter to sustain them. They need matter to display them, but they themselves exist equally well in perfect vacuum. How did they manage to spring into being? Can it be said that they too had existed previously in some dormant condition in the ether of space? That they too were closed loops opened out, and their existence thus displayed, by the electric current?