Skiascopy: A Treatise on the Shadow Test in Its Practical Application to the Work of Refraction, with an Explanation in Detail of the Optical Principles on which the Science is Based, with Sixty-nine Illustrations and Four Plates |
Other editions - View all
Skiascopy: A Treatise on the Shadow Test in Its Practical Application to the ... George Adelmer Rogers No preview available - 2016 |
Common terms and phrases
aberration accommodation aerial image ametropia area of light area of reversal astigmatic eye astigmatism axis banded appearance bring the area center of curvature concave mirror concave waves convex waves cornea correction crystalline lens curva cylinder diffusion at area diffusion circles diopter dioptric media dioptric power direction distance effect emergent pencils emitted pencils emmetropia emmetropic eye eye's fixed plane focal area foci focused glass horizontal hyperopia hyperopic image at area incident pencils increased index of refraction individual pencils intermediate meridians intervals inversion lenses luminous area magnification meter minor pencils modified motion nearer neutral pencils neutral waves object observed eye optical optician pencils of light plane mirror plane of reversal position posterior potential focus principal meridians produce pupil reflex resistance retina retinal image screen serving eye sine skiascopic skiascopist static refraction tion transposed vertical meridian virtual image wave speed waves of light
Popular passages
Page 74 - Eye are three in number : (1) the anterior surface of the cornea, (2) the anterior surface of the crystalline lens, and (3) the posterior surface of the crystalline lens (Fig 128). These surfaces act together like a convex lens, to bend 'the rays of light which pass through them (Fig. 132), so that all those which start from FIG. 132. — Illustrating the formation behind a convex lens of a diminished and inverted...
Page 5 - A Treatise on the Shadow Test in its Practical Application to the Work of Refraction, with an Explanation in Detail of the Optical Principles on which the Science is Based.
Page 141 - Flood and the Confusion of Tongues in the Building of the Tower of Babel.
Page 158 - ... have confined our attention to polarization phenomena observed along the lines of force. But it is well known that the doublets are, in general, transformed into triplets, when observed in a magnetic field at right angles to the lines of force. The components of the triplets are plane polarized, the central line in a plane at right angles to the plane of polarization of the side components. It should be possible to detect similar phenomena in spot spectra, if they are produced in a magnetic field....
Page 130 - ... rest upon the earth. MOMENTUM is the quantity of motion in a body. It is equal to the weight of the body multiplied by its velocity per second, expressed in feet. Ex. : A stone, weighing 5 Ibs., thrown with a velocity of 20 feet per second, has a momentum of 100 pounds. The striking force of a body is equal to its weight multiplied by the square of its velocity. (See p. 81.) Ex. : A bullet weighing 2 ounces, fired with a velocity of 1,400 feet per second, would strike with a force of 245,000...
Page 62 - But b/a = the ratio of wave speed in the other substance (.r) to wave speed in air, for the ratio of one quantity to another is the quotient obtained by dividing the...