an instrument for measuring the intensity of x-rays. Two series of plates, separated by an air gap that serves as the dielectric, are connected to opposite terminals in a closed chamber. An electric circuit is completed when the air becomes ionized by the roentgen rays, and the difference in electric potential is registered by deflection of a galvanometer needle.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.