For closely examining the cavities of the mouth and pharynx, the electrical laryngoscope will prove useful. Consisting of a small electric bulb and a concave mirror, the instrument is strapped to the physician's forehead, leaving his hands free for the examination. A laryngoscope is a rigid or flexible endoscope passed through the mouth and equipped with a source of light and magnification, for examining and performing local diagnostic and surgical procedures on the larynx.