interesting facts about: science
A periscope represents an optical instrument for observation around or through an object or obstacle that prevents direct observation from current position of viewer. In its primitive variant, periscope consists of a case with special mirrors within. Each mirror`s end is set parallel to each other at a angle 45-degree.
More complicated models of periscopes using prisms or advanced fiber optics instead of traditional mirrors, and supplying magnification, are used on naval transport (as ships, submarines etc.) and in different spheres of science. The design of the classical naval periscopes is not complicated: two telescopes are pointed into each other. Also, if the individual magnification of two telescopes differs, the difference between them causes an general reduction or magnification.
The history of periscopes knows more than 6 centuries of development. Apropos, Johannes Gutenberg, the famous inventor of printing machine (or as it was named by Catholic priests ”the Evil machine”), have sold a kind of periscope to pilgrims in the 1430s. Purposes of such periscopes use was very interesting, and now represents more historical funny story, but also it is a fact: Gutenberg`s periscopes… enabled to see over the heads of the crowd at the religious festivals in Germany an particularly at Aachen.
Johannes Hevelius, astronomer and engineer, described in 1647 another early model of periscope that used lenses in his main work Selenographia, sive Lunae descriptio (lat. Selenography, or describing of the Moon). Hevelius also was the first who saw military applications for his invention in the future. Finally, it was beginning to be possible since 1854, when Hippolyte Marié-Davy invented the first naval periscope. It consisted of a vertical tube with two mirrors fixed at each end at angle 45-degree. In World War I and World War II the effectiveness of periscope using was witnessed by many successful military operations organized with help of this device.