Refraction close refractionProcess by which a wave changes speed and sometimes direction upon entering a denser or less dense medium, eg a light ray changes direction when refracted by a lens. from a ...

Newton’s experiment remains almost insultingly simple. Sunlight, a darkened room, a glass prism. The conclusion was unavoidable. Colour belonged to light itself. The prism merely made it visible.

MR. C. D. AHRENS, the veteran prism-cutter, has lately devised a new type of liquid prism, which seems to have some advantages in optical work, both for direct-vision and for ordinary patterns of ...

THE Astronomer Royal, in his last communication to the Royal Astronomical Society on the Transits of Venus, adverted to the injurious effect on the observations, which might possibly arise from the ...