visible rays
1Visible spectrum — White light is dispersed by a prism into the colors of the optical spectrum. The visible spectrum is the portion of the electromagnetic spectrum that is visible to (can be detected by) the human eye …
2Visible horizon — Horizon Ho*ri zon, n. [F., fr. L. horizon, fr. Gr. ? (sc. ?) the bounding line, horizon, fr. ? to bound, fr. ? boundary, limit.] 1. The line which bounds that part of the earth s surface visible to a spectator from a given point; the apparent… …
3luminous rays — rays of the visible spectrum (see under spectrum) …
4Anticrepuscular rays — are similar to crepuscular rays, but seen opposite the sun in the sky. Sunlight travels in straight lines, but the projections of these lines on Earth s spherical atmosphere are great circles. Hence, straight line crepuscular rays from a setting… …
5Crepuscular rays — (  /krɨˈ …
6ultraviolet rays — invisible short wavelength radiation beyond the violet end of the visible spectrum. Sunlight contains ultraviolet rays, which are responsible for the production of both suntan and on overexposure sunburn. The dust and gases of the earth s… …
7Obscure rays — Obscure Ob*scure ([o^]b*sk[=u]r ), a. [Compar. {Obscurer} ([o^]b*sk[=u]r [ e]r); superl. {Obscurest}.] [L. obscurus, orig., covered; ob (see {Ob }) + a root probably meaning, to cover; cf. L. scutum shield, Skr. sku to cover: cf. F. obscur. Cf.… …
8Roentgen rays — X ray X ray, X ray X ray([e^]ks r[=a] ), n. [so called by its discoverer because of its enigmatical character, x being an algebraic symbol for an unknown quantity.] (Physics) originally, any of the rays produced when cathode rays strike upon… …
9X rays — X ray X ray, X ray X ray([e^]ks r[=a] ), n. [so called by its discoverer because of its enigmatical character, x being an algebraic symbol for an unknown quantity.] (Physics) originally, any of the rays produced when cathode rays strike upon… …
10Heat rays — Heat Heat (h[=e]t), n. [OE. hete, h[ae]te, AS. h[=ae]tu, h[=ae]to, fr. h[=a]t hot; akin to OHG. heizi heat, Dan. hede, Sw. hetta. See {Hot}.] 1. A force in nature which is recognized in various effects, but especially in the phenomena of fusion… …
