File:EB1911 Telegraph - Connexions for Double-current Working.jpg

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Description

English: The general arrangement of the connexions for double-current working; the galvanometer G is used for the purpose of indicating whether a station is calling, in case the relay sticks or is out of adjustment. The key K (shown in general plan), when worked, sends reversed currents from the battery B.

Date

published 1911

Source

Encyclopædia Britannica (11th ed.), v. 26, 1911, “Telegraph,” p. 517, Fig. 21.

Author

Harry Robert Kempe (section author)

Permission
(Reusing this file)

This image comes from the 13^th edition of the Encyclopædia Britannica or earlier. The copyrights for that book have expired in the United States because the book was first published in the US with the publication occurring before January 1, 1929. As such, this image is in the public domain in the United States.

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	Date/Time	Thumbnail	Dimensions	User	Comment
current	18:35, 19 February 2016		665 × 616 (83 KB)	Library Guy	{{Information \|Description ={{en\|1=The general arrangement of the connexions for double-current working; the galvanometer G is used for the purpose of indicating whether a station is calling, in case the relay sticks or is out of adjustment. The key...

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