ETYM Pref. peri- + -scope.
An optical instrument that provides a view of an otherwise obstructed field.
Optical instrument designed for observation from a concealed position such as from a submerged submarine. In its basic form it consists of a tube with parallel mirrors at each end, inclined at 45ş to its axis. The periscope attained prominence in naval and military operations of World War I.
Although most often thought of as a submarine observation device, periscopes were widely used in the trenches during World War I to allow observation without exposing the observer, and special versions were also developed to be attached to rifles. + prikaži više