Solar radiation measurements made on Sal in the Cape Verde Islands during the 1974 Gate project are analyzed in conjunction with aerosol size spectra data in order to describe the extinction and absorption of solar radiation by Saharan dust. From optical depth measurements, supported by Mie calculations, we were able to show that near-neutral extinction must exist across most of the solar spectrum as the result of a large effective scattering diameter of the dust. Absorption estimates were also made from our composite radiation data by inverting radiative transfer equations based on the data-Eddington model. Imaginary indices of refraction obtained by this method at three wavelengths agree satisfactorily with laboratory measurements made with Saharan dust. Total depletion of solar energy as a function of path lenght and optical depth is presented along with an analysis of the extinction coefficient as a function of aerosol concentrations. From the latter we determined a near-linear relationship between optical depth as measured at the ground and total aerosol loading in an atmospheric column. A brief comparison is made between aerosol extinction properties at Sal and at Barbados.