In 1854, Hippolyte Marié-Davy invented the first naval periscope, consisting of a vertical tube with two small mirrors fixed at each end at 45°.

How were periscopes used in ww1?

The trench periscopeis an optical device that soldiers used during the First World War to observe the ground in front of their trenches and fortifications, without taking the risk of raising their eyes above the parapet and creating a target for enemy snipers.

Do submarines still use periscopes?

Modern submarines are no longer built with the single rotating, one-person-at-a-time periscope that we're used to seeing in the movies. Instead, periscopes aboard the U.S. Navy's Virginia-class subs consist of two 360-degree rotating photonics masts with high-resolution cameras.