It is so common a notion nowadays that electricity had its birth and rise in the nineteenth century that it gives one a strange mental sensation to contemplate the fact that all the myriads of commercial applications that have of late years been developed in this field might have been made by the Chinese or the ancient Egyptians, so far as the potentiality of Nature for developing electrical phenomena is concerned. The writer used to know a delightful old gentleman in Vermont who once referred, as to a well-known fact, to Edison's having invented electricity. It is astonishing how closely his state of mind typifies that of a great many people. In the form of the lightning, the aurora, and the shock of the electric eel or torpedo, electrical manifestations have been known ever since man commenced to observe those phenomena, but the fossil resin amber was the substance which eventually gave its name to the now tremendous agency. This material was observed, many centuries before our era, to possess the property of attracting light bodies to itself when rubbed with wool, and, being called electron by the Greeks, transmitted its name to the property or force which it thus brought into evidence. The fact is mentioned as early as 600 B. C, by Thales of Miletus, although he does not transmit to us the name of the original observer of the phenomenon. Homely as was the experiment, it marked a beginning in electrical research.

Loins du tumulte urbain, Dans les montagnes de John Tyndall vous transporte au cœur des Alpes, entre sommets majestueux et glaciers étincelants.

La lumière solaire qui traverse une chambre obscure révèle sa trace en éclairant la poussière flottant dans l'air. « Le soleil, dit Daniel Culverwell, découvre les atomes que la lumière artificielle ne peut rendre visibles, et les montre à nu, s'agitant dans ses rayons. »Dans mes recherches sur la décomposition des vapeurs par la lumière, je fus forcé d'éliminer ces atomes et cette poussière. Il était absolument nécessaire que l'espace renfermant les vapeurs, n'embrassât aucune chose visible, qu'aucune substance capable de disperser la lumière au moindre degré sensible ne pût, à la fin d'une expérience, se retrouver dans le large tube qui.Fruit d'une sélection réalisée au sein des fonds de la Bibliothèque nationale de France, Collection XIX a pour ambition de faire découvrir des textes classiques et moins classiques dans les meilleures éditions du XIXe siècle.

The oldest historic reference to the rainbow is known to all: "I do set my bow in the cloud, and it shall be for a token of a covenant between me and the earth... And the bow shall be in the cloud; and I shall look upon it, that I may remember the everlasting covenant between God and every living creature of all flesh that is upon the earth." To the sublime conceptions of the theologian succeeded the desire for exact knowledge characteristic of the man of science. Whatever its ultimate cause might have been, the proximate cause of the rainbow was physical, and the aim of science was to account for the bow on physical principles... The condition requisite for their production is, that the drops which constitute the shower shall all be of nearly the same size. When the drops are of different sizes, we have a confused superposition of the different colors, an approximation to white light being the consequence. This second step in the explanation of the rainbow was taken by a man the quality of whose genius resembled that of Descartes or Newton, and who eighty-two years ago was appointed Professor of Natural Philosophy in the Royal Institution of Great Britain. I refer, of course, to the illustrious Thomas Young.

"The feelings and aims with which Newton and Goethe respectively approached Nature were radically different, but they had an equal warrant in the constitution of man. As regards our tastes and tendencies, our pleasures and pains, physical and mental, our action and passion, our sorrows, sympathies, and joys, we are the heirs of all the ages that preceded us; and, of the human nature thus handed down, poetry is an element just as much as science. The emotions of man are older than his understanding, and the poet who brightens, purifies, and exalts these emotions, may claim a position in the world at least as high and as well-assured as that of the man of science. They minister to different but to equally permanent needs of human nature; and the incompleteness of which I complain consists in the endeavor on the part of either to exclude the other. There is no fear that the man of science can ever destroy the glory of the lilies of the field; there is no hope that the poet can ever successfully contend against our right to examine, in accordance with scientific method, the agent to which the lily owes its glory. There is no necessary encroachment of the one field upon the other. Nature embraces them both, and man, when he is complete, will exhibit as large a toleration."