Further experiments on light

The author commences this account of his experiments by remarking, that “it is probable that some may consider the inference to be drawn from the following experiments as unfavourable to the doctrines of my former paper—I think I can explain the phenomena according to those doctrines —but be they ever so repugnant, we are of course in search of truth, and have no right even to wish that the balance may incline one way rather than another, far less to conceal any facts which may affect its inclination.” The leading experiment is this:—A speculum is placed in a beam of light and is inclined so that the reflected rays shall make a small angle with the surfaces.