Lumen. You are mistaken, my friend. The undulations of ether pass through obstacles that you would believe impenetrable. Clouds are formed of molecules between which rays of light frequently pass. In the contrary case, there are here and there vistas or gaps, across which one can only see obliquely. The case is very rare when nothing can be distinguished. Besides, light is not what it appears to be; it is a vibration of ether, and there are other ways of seeing than by means of the retina and the optic nerve.
The vibrations of ether are perceptible to senses other than those you possess. Therefore, if this be your sole objection, it is, I must say, far from being an insurmountable one.
Quærens. You have a special faculty for resolving all doubts. Perhaps this is one of the gifts granted to spiritual beings. I have been obliged successively to admit, that you have been transported to Capella with a swiftness exceeding that of light; that you reached another world as a spirit; that your soul is liberated from the flesh; that your ultra-earthly perception is able to distinguish from that height all that passes here; that you can advance or recede in space according to your fancy; and lastly, that the clouds themselves are no obstacles to your clearly seeing the surface of our globe. It must be owned that these are grave difficulties indeed.
Lumen. You are very material, my old friend! Should you be very surprised if I undertook to prove to you that all these difficulties exist only in name, and that all the objections which oppose themselves to your conception of phenomena are the effects of ignorance?
What should you think if I affirmed that no one has a single true idea of what takes place upon the Earth, and that man utterly fails to understand nature?
Quærens. In the name of all the indisputable truths of modern science, I should dare to think that you were trying to impose upon me.
The marvels of spectral analysis.
Piercing nature of the soul's sight.
Lumen. God forbid! Listen to me, my friend. The marvellous discoveries of contemporary science ought to enlarge the sphere of your conceptions. You have just discovered spectral analysis! By this methodic examination of a simple ray of light shot from a far-off star, you learn what are the elements which compose this inaccessible star and feed its brilliancy. This knowledge, my brother, is of more value than all the conquests of Alexander, of Cæsar, and of Napoleon, than all the discoveries of Ptolemy, of Columbus, of Gutenberg, than all the books of Moses and of Confucius. Only think, trillions of leagues span the abyss which separates us from Sirius, from Arcturus, from Vega, from Capella, from Castor and Pollux, and it is now possible to analyse the substances which constitute these suns, just as accurately as if you could take them in your hand and submit them to the crucible of the laboratory! How then can you refuse to admit that, by processes which are unknown to you, the soul's sight can be sufficiently piercing to see clearly a bright far-off world, and to distinguish even its smallest details? Does not the telegraph carry in an inappreciable moment your thought from Europe to America through the depths of the ocean? Cannot two people converse in a low voice at a distance of thousands of leagues, and still you hesitate to admit the truth of my narrations, because you do not altogether comprehend them? But can you explain how the telegraphic message is transmitted? No, you cannot. Cease then to retain doubts which have not even the merit of being scientific.