"The colors of the spectrum, then, "are not Qualifications [alterations] of Light … (as 'tis generally believed), but Original and connate properties." When you purchase through links on our site, we ...
Well, OK, not exactly. A beam of light could pass through air all day long (as long as you have a layer of air 26 billion kilometers long) and not deviate a whit. But if the density of that air ...