Читать книгу Kelly Miller's History of the World War for Human Rights - Kelly Miller - Страница 199

The periscope is distinctly a submarine device which is worthy of brief description. It is, in effect, a long tube, with an elbow joint at the top and a similar one at the bottom. At the elbow joints at both ends are arranged reflectors. The reflector in the upper end catches the object which comes within the range of vision, and reflects the image down the tube to the mirror at the lower elbow, where the pilot sees it. The principle of the periscope is the same as that of the "busybody," familiar to householders, and which is placed on the sill of an upper window, so that a person inside the house may see who is at the front door.

The Germans have recently devised a new form of periscope, designed to make the device invisible to the lookout of approaching boats. This device consists of two mirrors, put together like a "Y" lying on its side, the wide part in front. These skim through the waves and converge the image upon the low periscope's lens, which shoots the light down the tube to the receiving apparatus below. When looked at from a distance the mirrors reflect the surface of the sea, so that a lookout sees nothing but the waves as they are reflected in the mirror.

The Germans use the bottom of the sea as regular "land" for their supply bases, and when the submarines go to the surface it is precisely like an aeroplane mounting the air. The submarine fleet boasts also of "mother boats." They lie on the bottom of the ocean, in designated places, and rise at night to hand out their supplies. Crews are changed and tired men go back to the bottom to rest up, while fresher comrades take their places.

So, too, the submarine, with its ability to rest on the bottom of the sea, has become an efficient boat for mine laying. The mine layers work from the undersea boats without fear of disturbance, the divers walking out from the submarines to the floor of the sea without being seen or without ever coming to the surface.