the invention relates to periscopic apparatus for the observation and aiming or sighting apparatus , particularly for mounting on a vehicle , having a stabilized panoramic gunsight head positioned externally of the vehicle and a corresponding sight tube with at least one eye piece positioned within the said vehicle . the sight tube and the gunsight head are interconnected by a wall - traversing periscopic ferrule which can be substituted by a sleeve in which is placed either a nocturnal vision means or a ranging means or both of the said means .