George Biddell Airy to Faraday   17 October 1853

Royal Observatory Greenwich 1853 Octr. 17

My dear Sir

In speaking about the inductions among the parallel wires to and from Liverpool, I failed in conveying to you my conjectural reasons for supposing that there would be no induction1. I intended to express what I have diagrammatized on the following page (pray pity the mental struggles of a smatterer).

In case 1, the wire furnished with battery would produce a certain induction in the wire near it.

In case 2, I supposed that an induction of the opposite kind would be produced.

Therefore in case 3, I imagined that the effects of the two inductions would neutralise each other.

And case 4 (which is the case of wires to send from Liverpool) appeared to me to be, in the course of its currents, the same thing as Case 3: and thus I supposed that there would be no induction.

How many of these steps are erroneous?

Yours very truly | G.B. Airy

Professor Faraday

diagram

1
This refers to a set of experiments that Faraday, Airy and others had seen performed on 15 October 1853 at the Lothbury Wharf Office of the Electric Telegraph Company. The experiments were on long distance telegraphy and displayed the phenomena of telegraphic retardation. Faraday’s notes are in Faraday, Diary, 15 October 1853, 7: pp.401-8. For a discussion of this work see Hunt (1991).

Bibliography

HUNT, Bruce J. (1991): “Michael Faraday, Cable Telegraphy and the Rise of Field Theory”, Hist. Tech., 13: 1-19.

Please cite as “Faraday2742,” in Ɛpsilon: The Michael Faraday Collection accessed on 28 April 2024, https://epsilon.ac.uk/view/faraday/letters/Faraday2742