Fable has told us that the magicians of the East possessed mirrors in which they could at will produce images of the absent. Science now shows us that representations quite sufficient to deceive the credulous can be produced on the surface of polished metals without difficulty. A highly polished plate of steel may be impressed with images of any kind, which would remain invisible, the polished surface not being in the least degree affected, as it regards its reflecting powers; but by breathing over it, the dormant images would develope themselves, and fade away again as the condensed moisture evaporated from the surface.[135] These, which are but a few selected from a series of results of an equally striking character, serve to convince us that nature is unceasingly at work, that every atom is possessed of properties by which it influences every other atom in the universe, and that a most important class of natural phenomena appear to connect themselves directly with the radiant forces. The alchemists observed that a change took place in chloride of silver exposed to sunshine. Wedgwood first took advantage of that discovery to copy pictures. Niepce pursued a physical investigation of the curious change, and found that all bodies were influenced by this principle radiated from the sun. Daguerre produced effects from the solar pencil which no artist could approach to; and Talbot and others extended the application. Herschel took up the inquiry; and he, with his usual power of inductive search and of philosophical deduction, presented the world with a class of discoveries which showed how vast a field of investigation was opening for the younger races of mankind,--a field in which a true spirit may reap the highest reward in the discovery of new facts, and to which we must look for a further development of those great powers with which we have already some slight acquaintance, and for the discovery of higher influences which are not yet dreamed of in our philosophy. If music, with its mysteries of sound, Gives to the human heart a heavenward feeling; The beauty and the grandeur which are found Spread like a vesture this fair earth around, Creation’s wond’rous harmonies revealing, And to the soul in truth’s strong tongue appealing, With all the magic of those secret powers, Which, mingling with the lovely band of light, The sun in constant undulation showers To mould the crystals, and to shape the flowers, Or give to matter the immortal might Of an embracing soul--should, from this sod, Exalt our aspirations all to God. FOOTNOTES: