1.—Account of Experiments to ascertain the amount Prof. Wm. Thomson's “Solar Refraction.”

Extract

After alluding to the excessive difficulty of ascertaining the presence and nature of a resisting medium in space, by planetary or cometary perturbations, the author reminded the meeting of the statements made in those rooms last year, that one of the consequences to which the dynamical theory of heat had led him, was the necessity of the existence of a medium filling space; that such medium was but an extension of our own atmosphere, and must experience a condensation in the neighbourhood of the sun; and that there must consequently arise a certain refraction of any heavenly body seen through such medium.