Page:Collected Physical Papers.djvu/382

362 The extreme sensitiveness of the Radiometer was also exhibited by its discrimination of the radiation components of the morning and midday light. In the morning the intensity of the blue rays in the spectrum was found to be slightly less than at midday. This is due to the greater scattering of the short waves by the thicker stratum of the atmosphere through which the light has to pass in the morning.

The energy of radiation in the different regions of the spectrum was compared on January 16 and 19, 1923. It should be remembered that the determination of the energy of the different rays was made upon the spectrum given by the carbon disulphide prism. The following results for the 16th and 19th January are seen to be practically the same.

Table showing the Distribution of Energy in the Spectrum produced by the CS2 Prism