What are anechoic tiles?

Some articles on anechoic tiles:

Anechoic Tile - Development By Nazi Germany
... The technology of anechoic tiles was developed by the Kriegsmarine in the Second World War ... Ultimately only one operational Type XXIII, U-4709, was coated with the anechoic tiles ... U-boats with the anechoic tiles coating include U-11, U-480, U-485 U-486, U-1105, U-1106, U-1107, U-1304, U-1306, U-1308, U-4704, U-4708 and U-4709 ...

Famous quotes containing the word tiles:

    I learn immediately from any speaker how much he has already lived, through the poverty or the splendor of his speech. Life lies behind us as the quarry from whence we get tiles and copestones for the masonry of today. This is the way to learn grammar. Colleges and books only copy the language which the field and the work-yard made.
    Ralph Waldo Emerson (1803–1882)