Volume II · 10 landmarks

Electronics

Charge under control: batteries, lamps, tubes, and the first computers.

1. 

   1800Voltaic pileVolta stacked disks of silver and zinc, separated by cloth soaked in brine, and drew a steady current.

2. 

   1831 (Faraday); commercial dynamos 1870sDynamoMove a conductor in a magnetic field and a current appears.

3. 

   1878–1879 (Swan and Edison practical lamps)Electric lightA filament in a vacuum glows when current heats it, without burning up at once.

4. 

   1895–1906RadioA spark, an antenna, a coherer or later a tube: wireless telegraphy threw Morse across a gap with no wire between.

5. 

   1904 (Fleming valve); 1906 (De Forest triode)Vacuum tubeA heated filament in a vacuum emits electrons.

6. 

   1935 (British Chain Home era)RadarSend a radio pulse; listen for the echo; time is distance.

7. 

   1940s (Colossus, ENIAC, Manchester)Electronic digital computerA computer is a machine that follows a stored program of arithmetic and logic.

8. 

   1947TransistorIn December 1947 three researchers at Bell Labs built a small sandwich of germanium that could switch and amplify a signal without a glowing glass tube.

9. 

   1991 (Sony commercial cell)Lithium-ion batteryLithium is light and eager to shed an electron.

10. 

    2007 (iPhone as mass template)SmartphoneA smartphone is a pocket computer that is also a radio, a camera, a map, and a store of other people’s software.