...What appearance have the moons or jplanets, when their disks are magnified by the aid of a telescope ? When a ray of light passes out of one medium into another, is it turned out of its former course ? If it does, how can it be proved ? With what is the earth surrounded...

...angle is the same for all distances of the eye. 183* 145. Explain the experiments by which it appears that when a ray of light passes out of one medium into another, the sine of incidence is to the sine of refraction in a given ratio ; and that if the refracted ray becomes...

...refracted rays. is turned back into the medium in which it was moving, it is said to be reflected. 7. When a ray of light passes out of one medium into another, and has its direction changed at the common surface of the two media, it is said to be refracted. 8....

...constant ratio to each other, whatever the obliquity may be. This is precisely the same thing as saying, that when a ray of light passes out of one medium into another, the sine« of the angles of incidence and refraction, always p1*" serve a constant ratio for every variety...

...submerged will come to the eye, as if from a point nearer to the surface than the point itself. 32. When a ray of light passes out of one medium into another, as the angle of incidence increases, the angle of deviation also increases. Let 0 be the angle of incidence,...

...Rays on plane Surfaces. — The Prism. — Action of the Prism on a Ray. — The Multiplying- Glass. WHEN a ray of light passes out of one medium into another of a different density, its rectilinear progress is disturbed, and it bends into a new path. This phenomenon...

...a ray incident parallel to one of them may after reflexion at each be parallel to the other ? . 8. When a ray of light passes out of one medium into another, as the angle of incidence increases the angle of deviation also increases. 9. A ray of light is refracted...

...2, 1, and concave to the surface of the earth. 81. VARIATION OF REFRACTION IN RESPECT TO ALTITUDE. When a ray of light passes out of one medium into another, the more obliquely it strikes the surface of the second medium the more it is refracted, and if it falls...

...convex mirror are made to diverge more than before reflection. SECTION III. REFRACTION OF UGHT. 417. When a ray of light passes out of one medium into another of a different density, it changes its direction at the point which separates the two media. This phenomenon...

...2, 1, and Concave to the surface of the earth. 81. VARIATION OF EEFRACTION IN RESPECT TO ALTITUDE. When a ray of light passes out of one medium into another, the more obliquely it strikes the surface of the second medium the more it is refracted, and if it falls...