"Variations de conductibilite sous diverses influences electriques" in Comptes Rendus de l'Academie des Sciences.

Branly, Edouard. ++Invention of the Coherer, a Crucial Element in the Invention of Radio++

Published by Gauthier-Villars, 1890

About this Item

Branly, Edouard. "Variations de conductibilite sous diverses influences electriques" in Comptes Rendus de l'Academie des Sciences, Paris, Gauthier-Villars, 1890, volume 111 (July-December), 1171pp. With the Branly appearing on pp.785-787. The Branly paper is found in this half-yearly bound volume of the Comptes Rendus, in the original wrappers, and with the seldom scene original spine label. There are a few very minor complaints to the binding; the text is fresh and crisp, and very largely unopened. A solid VG copy (7/10). The volume is housed in a new folding clamshell case, with calf-backed boards and calf hinges. A fine piece of bookbinding, brand new. [++] This is the first and most important paper Branly published on his coherer between 1890-1897 (when at least four other paers were published by him on the coherer. a crucial element in the development of radio communications. [++] The Branly Coherer, (aka the Branly Tube or Branly's Radio Conductor), was an early device used in the development of wireless telegraphy, invented by Edouard Branly (1844-1940) in 1890, which played a crucial role in the history of radio and paved the way for the development of more advanced technologies in the field of telecommunications. (Marconi mentioned the importance of Branly's contribution in his first wireless transmission across the English Channel.) The Coherer played a significant role in the early development of wireless telegraphy and a key component in the reception of radio waves. It consisted of a glass tube filled with metal filings or other conducting materials such as iron and silver. The metal filings loosely packed inside the tube formed a conductive path in its natural state. When electromagnetic waves, generated by a transmitter or atmospheric disturbances, passed through the coherer, the electrical resistance of the filings inside the tube decreased, causing the coherer to become conductive. This change in conductivity was then used to trigger a signal or sound in a connected receiver. $750.

Seller Inventory # ABE-1740758995734

Bibliographic Details

• Title: "Variations de conductibilite sous diverses influences electriques" in Comptes Rendus de l'Academie des Sciences.
• Publisher: Gauthier-Villars
• Publication Date: 1890
• Binding: Soft cover
• Edition: 1st Edition
• Condition: Very Good
• Weight: 3 pounds
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