What people are saying - Write a review
We haven't found any reviews in the usual places.
Other editions - View all
angle angle of incidence aperture appear augmented axis bands beam becomes blue bodies bright called candle cast caused centre colours concave convergent convex corresponding crystal dark determined diminish direction distance divergent divided double drawings effect employed enclosed enters equal ether example experiments falling feet flame focus follows formed front glass greater heat Hence Iceland spar illuminated intensity intersect inverted lens less light looked luminous means metal mirror moon motion moves object obliquely observer obtained optic ordinary parallel particles pass perpendicular placed plane plate polarized portion position principal focus prism produce pupil ratio rays reaches receive reflected reflexion refraction rendered retardation retina rings round screen seen shadow side sine slit solar space spectrum spherical square straight strike substance Supposing surface theory thickness transmitted transparent velocity vibration visible vision waves
Page 8 - It may also be defined as the sine of the angle of incidence divided by the sine of the angle of refraction, as light passes from air into the substance.
Page 68 - SOUND: a Course of Eight Lectures delivered at the Royal Institution of Great Britain.
Page 67 - Notes of a Course of Nine Lectures on Light, delivered at the Royal Institution, AD 1869. By Professor TYNDALL. Crown 8vo.
Page 23 - The justification of a theory consists in its exclusive competence to account for phenomena. On such a basis the Wave Theory, or the Undulatory Theory of Light, now rests, and every day's experience only makes its foundations more secure. . . . This substance is called the luminiferous ether.
Page 28 - It is worth while to mark how this experiment illustrates the fact that, however intense a luminous beam may be, it remains invisible unless it has something to shine upon. Space, though traversed by the rays from all suns and all stars, is itself unseen. Not even the ether which fills space, and whose motions are the light of the universe, is itself visible.
Page 27 - ... is 474,439,680,000,000. All these waves enter the eye in a second. In the same interval 699,000,000,000,000 waves of violet light enter the eye.
Page 24 - In the case of sound, the vibration of the airparticles are executed in the direction in which the sound travels. They are therefore called longitudinal vibrations. In the case of light, on the contrary, the vibrations are transversal; that is...
Page 65 - I have endeavoured to place before you with the utmost possible clearness the basis of the undulatory theory, do I therefore wish to close your eyes against any evidence that may arise of its incorrectness ? Far from it. You may say, and justly say, that a hundred years ago another theory was held by the most eminent men, and that, as the theory then held had to yield, the undulatory theory may have to yield also. This is perfectly logical. Just in the same way, a person in the time of Newton, or...
Page 23 - OF THOMAS YOUNG, MD, FELLOW AND FOREIGN SECRETARY OF THE ROYAL SOCIETY, MEMBER OF THE NATIONAL INSTITUTE OF FRANCE; A MAN ALIKE EMINENT IN ALMOST EVERY DEPARTMENT OF HUMAN LEARNING. PATIENT OF UNINTERMITTED LABOUR, ENDOWED WITH THE FACULTY OF INTUITIVE PERCEPTION, WHO...