We could add many others to this list. But enough. And yet we have not said the last word on the subject. We have to discuss the interchange of sympathetic currents, and those which are the reverse, taking place between the electricity of the skies and that of the telegraph. Lightning often comes incognito to visit the earth's surface, or even the depths of the ocean. These little excursions to our terrestrial dominions usually pass unperceived; however, in certain cases the telegraph wires commit the indiscretion of revealing them. On the other hand, we know that the wires entrusted with carrying our thoughts round the world, are almost inconceivably sensitive. Without being conscious of the fact, they are in correspondence with the sun, 149 millions of kilometres away, and any agitation on the surface of this luminary may cause them indescribable agitation, as we witnessed at the close of the year 1903. During the formidable magnetic tempest of the 31st October, telegraphic and telephonic communication were interrupted in many parts of the world. In fact, the phenomenon was observed all over the surface of the globe. From nine o'clock in the morning, till four in the afternoon, the old world and the new were strangers to one another. Not a word nor a thought crossed the ocean; the submarine cables were paralyzed on account of solar disturbances. In France, communication between the principal towns and the frontiers was interrupted. During this time the sun was in a condition of violent agitation, and its surface vibrated with intense heat. In such times the subtle fluid profits by the confusion to glide noiselessly along the paths which are open to it. But he does not always wait for these favourable opportunities. Let a thunder-cloud pass over the telegraph wires, either noiselessly or hurling petards in all directions, the line will be affected. The fluid imprisoned in the sky will act by induction on the electricity of the wires which will result in the vibration of the latter, accompanied sometimes by a flash of lightning. These phenomena may cause grave accidents to the telegraph clerks, unless they are on their guard against the treachery of the lightning. These mute discharges happen frequently, but the spark strikes the telegraph wires often, too, as well as the apparatus in the office. All sorts of accidents result from these repeated attacks. We know, for instance, how the birds fall victims to the lightning when they alight on the telegraph wires after a thunderstorm; they are often found dead hanging by their claws. But the fluid acts on man also, through the medium of the wires.