X-rays

—Roentgen rays; a peculiar radiation po e ing remarkable properties discovered by Roentgen in 1895, while experimenting with a highly exhausted Crookes tube. These rays are projected from a target within the tube against which the rays from the cathode are directed, and are found to differ from any form of radiation hitherto known. They pa readily through many, substances opaque to light; they act on an ordinary photographic plate; they are incapable of reflection, refraction or polarization; they produce brilliant fluorescence on certain substances; they render the air a conductor of electricity, and cause painful trouble on the human skin if too long exposed to them.