In his native North-East England Joseph Swan is world-famous for inventing the incandescent light bulb. He also made significant contributions to the development of photography.

Joseph Wilson Swan was born to John and Isabella Swan in Bishopwearmouth, near (now in) Sunderland on October 31, 1828 and died on May 27, 1914 in Warlingham, in Surrey.

At the age of 13 he was taken on as apprentice in a pharmacists' in Sunderland. His apprenticeship ended after six years when the two partners of the firm of Hudson and Osbaldiston to which he was apprenticed died, whereupon Swan joined John Mawson as a partner in his pharmaceutical manufacturing firm in Newcastle upon Tyne.

The Incandescent Light Bulb

Swan's interest in the development of electric lighting dated from the 1840's. Starting in 1850 he experimented with various bulb designs using carbon filaments derived from paper or adapted from the carbon rods used in arc lamps. Although he succeeded in producing a demonstration bulb as proof of principle and patented the invention in 1860, the design was not suitable for use in practical applications. Vacuum pump technology was insufficiently developed and it was only possible to produce a bulb with a partial vacuum. The residual oxygen inside the bulb reacted with the hot carbon filament, shortening its life. To mitigate this problem, the bulb had to be operated at a relatively low temperature, producing a dim reddish light.

By the mid 1870s better vacuum pumps were available. Swan returned to the problem and developed a bulb with a higher vacuum and a carbon filament made from a thread, which he patented in 1878 and demonstrated to the Newcastle Chemical Society in February 1879. Given the lack of oxygen in the bulb the filament could not burn and could therefore be run at a high enough temperature to glow white hot.

In the same year he began promoting his bulb by illuminating prominent houses and landmarks around England, and in 1880 gave an impressive large-scale public exhibition of electric lamps in Newcastle.

Swan's 1879 bulbs still differed in one important point of principle from those that are used today: his filaments were relatively low in resistance, which meant that they drew a large current. The heavy current load meant that the wires supplying them had to be fairly thick. Over in America, Thomas Edison had presented a high resistance low current bulb in October of 1879. After 1879 Swan also worked on high resistance filaments, patenting one made of cellulose in 1881. While he was at it, he invented a process for extruding nitrocellulose to make the fibres he needed for the filaments, which was adopted by the textiles industry to make artificial silk. In 1881 he started commercial production of his light bulbs with his own company, the Swan Electric Light Company. Cellulose filaments became the industry standard.

In 1882 Swan sold his US Patents to the Brush Electric Company. In 1883 Swan's company merged with Edison's in Britain to form the Edison & Swan United Electric Light Company, generally known as 'Ediswan.' Edison would have preferred to go it alone, but the patents were against him. In the end, Edison bought Swan out. As a result, Swan no longer had any involvement in the manufacture and marketing of the light bulb. This no doubt had an influence on later perceptions of his technical contribution.

Outside of North-East England, Edison tends to be given the credit for the invention of the light bulb, although he developed it later than Swan. One reason for this is that it was the high-resistance filament that made it possible to connect light bulbs to practical higher voltage electrical transmission systems. Another was that Edison and his successors in General Electric had better marketing.

Photography

Joseph Swan also made significant contributions to the development of photography. In 1871 he developed dry photographic plates, a major step forwards in convenience, and in 1879 patented bromide paper.

Honours

Swan was elected to the Royal Society in 1894 and knighted in 1904. There are schools, roads and the usual etcetera named after him in North-East England.


Sources: http://en.wikipedia.org/wiki/Joseph_Swan; http://chem.ch.huji.ac.il/~eugeniik/history/swan.html; http://en.wikipedia.org/wiki/Incandescent_light_bulb; http://www.wearsideonline.com/Famous_People.1.html; childhood in Newcastle, general knowledge and logic. There needs to be more on photography here but the sources I have found so far are internally inconsistent and technically suspect.

Log in or register to write something here or to contact authors.