The Age of Vacuum Tubes: The Conquest of Analog Communications [Historical]

After they first appeared on the scene in the early 1900s [1], a series of improvements on vacuum tubes occurred in the second decade of the 20th century, leading them to maturity. A major advancement was introduced by an American chemist and physicist Irving Langmuir (18811957) of the GE Research Laboratory in 1912, who used his new mercury vapor diffusion pump to obtain high vacuum tubes. These proved much more durable, reliable, and capable of linear amplification at high frequencies, thus opening the way to their wider application. Langmuir, who obtained his doctorate under Nobel laureate Walther Nernst in Göttingen, Germany, (perfecting in Europe was a common practice among talented American researchers of the time: top scientists Joshia W. Gibbs and Henry A. Rowlands did the same) was the first to explain the theory of the device and developed it into a tube dubbed Pliotron (De Forest, the inventor of Audion, erroneously thought that residual gas was essential for its conduction). After introducing inert-gas filling of incandescent bulbs in 1913, thus greatly lengthening their lifetime and assuring huge incomes for GE, he was let free to follow his research interests in surface chemistry, which ultimately led him to the Nobel Prize in 1932, the first awarded to an industrial chemist.