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lightning rod

(Encyclopedia)lightning rod, a rod made of materials, especially metals, that are good conductors of electricity, which is mounted on top of a building or other structure and attached to the ground by a cable. By v...

lightning

(Encyclopedia)lightning, electrical discharge accompanied by thunder, commonly occurring during a thunderstorm. The discharge may take place between one part of a cloud and another part (intracloud), between one cl...

rod

(Encyclopedia)rod: see English units of measurement. ...

lightning bug

(Encyclopedia)lightning bug: see firefly.

divining rod

(Encyclopedia)divining rod or dowser, stick used in searching for underground water or minerals. This form of divination is still in common use in many parts of the world. The instrument is typically a forked twig....

Aaron's-rod

(Encyclopedia)Aaron's-rod, popular name for several tall-flowering, infrequently branching plants, such as goldenrod and mullein. The name is an allusion to the rod that Aaron placed before the ark and that miracul...

Laver, Rod

(Encyclopedia)Laver, Rod (Rodney George Laver) lāˈvər [key], 1938–, Australian tennis player. He left school at age 15 to pursue tennis and in 1962 became the first male grand-slam winner in tennis since Don B...

thunder

(Encyclopedia)thunder, sound produced along a path of a lightning flash, caused by the rapid heating and expansion of the adjacent air; lightning can heat air to temperatures as much as five times hotter than those...

triangle , in music

(Encyclopedia)triangle, in music, percussion instrument consisting of a steel rod bent into a triangle, open at one angle, and struck with a steel rod. Only since the end of the 18th cent. has it been an orchestral...

electroscope

(Encyclopedia)electroscope, device for detecting electric charge invented by Nollet in 1748. There are various types of electroscopes. The most common has a cylindrical metal case closed by two round, flat, glass f...