Page:The Swiss Family Robinson (Kingston).djvu/53

Rh there had been little or no twilight. This convinced me that we must be not far from the equator, for twilight results from the refraction of the sun's rays; the more obliquely these rays fall, the further does the partial light extend, while the more perpendicularly they strike the earth the longer do they continue their undiminished force, until, when the sun sinks, they totally disappear, thus producing sudden darkness.