 | William Chauvenet - 1874 - 724 pages
...not of uniform density, but is most dense near the surface of the earth, and gradually decreases iu density to its upper limit, where it is supposed to...16, the ray Se from a star, entering the atmosphere tt e, is bent into the curve ecA which reaches the observer at A in the direction of the tangent S'A... | |
 | William Chauvenet - 1874 - 724 pages
...density to its upper limit, where it is supposed to be of such extreme tenuity that its first eft'ect upon a ray of light may be considered as infinitesimal....the ray Se from a star, entering the atmosphere at «, is bent into the curve ecA which reaches the observer at A in the direction of the tangent S'A... | |
 | Nathaniel Bowditch - 1888 - 704 pages
...earth. The last direction of the ray is that of a tangent to the curved path at the eye of the observer, and the difference of the direction of the ray before...the atmosphere and this last direction is called the refraction. Art. 249. To illustrate this, let MN (Fig. 62) repre sent the strata of the earth's atmosphere;... | |
 | William Chauvenet - 1891 - 716 pages
...atmosphere be regarded as a vacuum, or as filled with a medium which exerts no sensible effect upon the direction of a ray of light, the path of the ray will...astronomical refraction, or simply the refraction. Thus, Fig. 10, the ray Se from a star, entering the atmosphere at e, is bent into the curve e.cA which reaches... | |
 | William Chauvenet - 1891 - 714 pages
...to the second law above stated, the new medium being the denser, the ray will be beiit towards thp normal, which in this case is a line drawn from the...the ray Se from a star, entering the atmosphere at «, is bent into the curve ecA which reaches the observer at A in the direction of the tangent S'A... | |
 | Nathaniel Bowditch - 1906 - 670 pages
...earth. The last direction cf the ray is that of a tangent to the curved path at the eye of the observer, and the difference of the direction of the ray before entering the atmosphere and this last direction constitutes the refraction. 297. To illustrate this, consider the earth's atmosphere as shown in figure... | |
 | Nathaniel Bowditch - 1916 - 912 pages
...earth. The last direction of the ray is that of a tangent to the curved path at the eye of the observer, and the difference of the direction of the ray before entering the atmosphere »nd this last direction constitutes the refraction. 297. To illustrate this, consider the earth's... | |
 | John William Norie, J. W. Saul - 1917 - 642 pages
...light from a star in coming to the observer must pass through the atmosphere which surrounds the earth. The atmosphere, however, is not of uniform density,...entering the atmosphere and this last direction is called simply the refraction, or occasionally the refraction in altitude. In Fig. 3, let AT represent the... | |
 | Nathaniel Bowditch - 1920 - 840 pages
...earth. The last direction of tho ray is that of a tangent to the curved path at the eye of the observer, and the difference of the direction of the ray before entering the atmosphere and this last direction constitutes the refraction. 297. To illustrate this, consider tho earth's atmosphere as shown in figure... | |
 | Nathaniel Bowditch - 1931 - 866 pages
...110.47. The last direction of the ray is that of a tangent to the curved path at the eye of the observer, and the difference of the direction of the ray before entering the atmosphere and this last direction constitutes the refraction. To illustrate this, consider the earth's atmosphere as shown in figure... | |
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The atmosphere, however, is not of uniform density, but is most dense near the surface of the earth, and gradually decreases in density to its upper limit, where it is supposed to be of such extreme tenuity that its first effect upon a ray of light may... 