Vietnam or Thailand ? Vote for the TOP Country of the Week !
Updated: June 18, 2025
As constructed by Fresnel, the hypothesis of the luminous ether, which had so great a struggle at the outset to overcome the stubborn resistance of the partisans of the then classic theory of emission, seemed, on the contrary, to possess in the sequel an unshakable strength.
Arago at once recognized the merit of Fresnel's work, and soon became a convert to the theory. He told Fresnel that Young had anticipated him as regards the general theory, but that much remained to be done, and he offered to associate himself with Fresnel in prosecuting the investigation.
It was the study of the phenomena of polarization which led Fresnel to his bold conception of transverse vibrations, and subsequently induced him to penetrate further into the constitution of the ether. We know the experiment of Arago on the noninterference of polarized rays in rectangular planes.
Five minutes later Fresnel was securely bound to a chair, and effectively silenced by a very uncomfortable gag improvised out of a block of wood and a muffler. On the threshold the departing Andre-Louis turned. "Good-night, Fresnel," he said. Fierce eyes glared mute hatred at him. "It is unlikely that your ferry will be required again to-night.
A most remarkable verification fell to the lot of the late Sir William Hamilton, of Dublin, who, taking up the theory where Fresnel had left it, arrived at the conclusion that at four special points of the 'wave-surface' in double-refracting crystals, the ray was divided, not into two parts but into an infinite number of parts; forming at these points a continuous conical envelope instead of two images.
What is to be thought of the contemporary of Young and of Fresnel, who never misses an opportunity of casting scorn upon the hypothesis of an ether the fundamental basis not only of the undulatory theory of light, but of so much else in modern physics and whose contempt for the intellects of some of the strongest men of his generation was such, that he puts forward the mere existence of night as a refutation of the undulatory theory?
In the year 1820, in the course of some investigations connected with the Trigonometrical Survey of Great Britain, and conducted by a deputation of scientific persons from London and Paris, M. Fresnel exhibited from the French side of the channel, by means of his lens and a large lamp, a powerful light which was observed by the English across the channel.
In applying this light to reflectors it is intended to use three small flames, each about three-eighths of an inch in diameter, productive, it is said, of an effect equal to that of ten Argand lamps. But for lenses the burner has seventeen films of flame, and is said to possess six times the power of the Fresnel lamp.
This thought, however, presents few difficulties to the mind accustomed to philosophical speculation. But the question early arose in the mind of Fresnel whether the ether is not considerably affected by contact with the particles of solids.
He bethought him of a pistol pressed upon him by Le Chapelier at the moment of his leaving Rennes, a gift which at the time he had almost disdained. True, it was not loaded, and he had no ammunition. But how was Fresnel to know that? He acted quickly. As with his right hand he pulled it from his pocket, with his left he caught the ferryman by the shoulder, and swung him round.
Word Of The Day
Others Looking