Edison & the Carbon Lamp

[brian whatcott <inet@intellisys.net>]

> ... I think there is lots of, um, enlightening
> discussion which can emerge from contemplation of the engineering
> marvel that has evolved since its invention by the Wizard of
> Menlo Park.
>
> Leigh

....I quote below what seems to be a relatively balanced account of the 
carbon filament lamp's development contributed recently to a list for
 the history of scientific instruments, at some point after I casually 
mentioned that Edison read about a carbon lamp in the pages of 
Scientific American, hehe:


"Ediswan was a trade name of the Edison & Swan United Electric Lighting Co,
the company formed in Britain in 1883 when the separate Swan and Edison
companies agreed to sink their differences and cease litigating against one
another. The combined company then used the courts to enforce its monopoly
on the production of carbon filament lamps until Edison's patents expired.
Nevertheless, the vast majority of lamps produced by the company were to
Swan's design, not Edison's.

"Joseph Swan developed a carbon filament lamp at about he same time as
Edison. Chauvinistic Englishmen would say before Edison, just as
chauvinistic Americans would deny there could be any competition with
Edison. Truth is more complex. There is no single moment of invention for
something like the filament lamp, and by far the most probable version of
events is that several men (Maxim and Lane-Fox as well as Edison and Swan)
developed usable high-resistance carbon filament lamps at about the same
time and more or less equally independently of one another or anyone else.
Their subsequent commercial success, or failure, is another matter. Swan's
first attempts did use a carbon rod, but he moved on from that and the lamps
he put on the market used filaments made from cotton thread treated in a
particular way and then  carbonised. He did not promote a particular
lighting system himself, but the installations of his lamps certainly had
the lamps in parallel, with suitably designed generators from other
companies. This should be well known. The Edison and Swan companies in
Britain certainly combined for business advantage, but why did Edison agree
to settle with another company in this case and to the best of my knowledge
this one only. Could it possibly be that there was doubt as to whether he
could win a case against Swan in the British courts? I do not think this
question has ever been seriously investigated.

"After Edison's patents expired the Edison and Swan company felt the chill
wind of competition. It continued to make carbon and, later metal, filament
lamps and other products, I believe until after the Second World War, but it
was not an innovative company. There was no special Ediswan lighting system,
but the company did produce some specialist products. One of these was the
"Pointolite" lamp, with its control gear, a very compact light source
suitable for use as a microscope illuminant. 

"There is a small number of Ediswan catalogues from the 1930s or thereabouts,
and at least one earlier Swan catalogue held with the Lighting Collection at
the Science Museum in London. There is a detailed account of Swan's work in
"J. W. Swan and the Invention of the Incandescent Electric Lamp" by C. N.
Brown, published by the Science Museum in London in 1978. Anyone interested
in Edison's marketing techniques should read "Thomas Edison's Parisian
Campaign: Incandescent Lighting and the Hidden Face of Technology Transfer"
by Robert Fox in "Annals of Science", vol. 53, 1997, pp. 157-193. There is a
lot about the origins of the filament lamp from a point of view relatively
independent of both Britain and America in "The history of N.V. Philips'
gloeilampenfabrieken Vol.1. The origin of the Dutch incandescent lamp
industry" by A. Heerding, translated by Derek S. Jordan published by
Cambridge University Press, Cambridge UK.



Neil Brown

*******************************************************
C. N. Brown,
Senior Curator - Classical Physics,
Science Museum,
South Kensington,
London,  SW7 2DD.
*******************************************************


Sincerely
Brian Whatcott