Bug Off

This article focuses on innovations done by engineers for spying. If there has been espionage, engineers have been a part of it. In World War II, infiltrators and downed pilots had to be able to find their way behind enemy lines. Compasses were hidden in cufflinks, pencil clips, and buttons. Maps were printed on rice paper so they wouldn't rustle when opened. British pilots wore special flying boots with cutaway tops that, when removed, left normal-looking shoes. Bugging is another method of the spy. The purpose of a bug is to detect sound vibrations in air or in other materials, such as wood, plaster, or metal. A good bug must reject unwanted noise, be easily concealed, and be energy efficient. The United States had an entire listening kit in the 1950s and 1960s with an assortment of accessories like a tie clip and wristwatch microphones.