Joseph Swan was a chemist, physicist, and inventor, who is most famous for his important role in the development of electric lighting. In 1860 Swan developed a carbon-filament incandescent lamp (some twenty years before Edison!!) and in 1878, produced an all-glass hermetically sealed bulb. He also invented a dry photographic process. This invention lead to a huge improvement in photography and progress toward the development of modern photographic film.
Joseph Swan was born in Sunderland, England on October 31, 1828 to John and Isabella Swan. A particularly inquisitive child interested in creative endeavors, he began an apprenticeship with a pharmacist when he was 13. He served six years as an apprentice to a Sunderland firm of druggists, Hudson and Osbaldiston. However, both partners died, and Swan joined John Mawson, who had founded a pharmaceutical business in Newcastle upon Tyne in the year that Swan was born. This company existed as Mawson Swan and Morgan until recently. Joseph Swan worked at the company premises at 13 Mosley Street.
From an early age, Swan was keen to learn about new inventions. He used Sunderland library to read about Starr’s electric lamp, patented in 1845, but unsuccessful because it blackened too quickly. He also learned about new photographic processes such as electrotyping and daguerreotypes. Mawson encouraged Swan to pursue his scientific investigations, and introduced him to local chemical manufacturers. They built a small laboratory at the top of the house above the shop. As Swan was gaining interest in photography, he began to make collodion, which became a speciality of the company. “Mawson’s Collodion” was launched in 1854. Mawson took Swan into partnership in 1846.
Invention of an incandescent bulb for electric lighting
Beginning in the 1840s Swan undertook his most important studies. It was at this time that he began his experiments with incandescence for illumination purposes. Swan experimented in the 1850s and 60s with carbon filaments. His early efforts failed however, because the vacuum pumps of those years could not remove enough air from the lamps.
Made from an arc-lamp element, Swan’s carbon rod gave off light but did not last very long. Gasses trapped in the rod were released when the lamp was activated, and a dark deposit of soot quickly built up on the inner surface of the glass. So while Swan’s lamp worked well enough for him in a demonstration, it was impractical in actual use. By the mid-1870s better pumps became available, and Swan returned to his experiments.
Swan’s historic lightbulb
By late 1878, Swan reported success to the Newcastle Chemical Society and in February 1879 demonstrated a working lamp in a lecture in Newcastle. The most significant feature of Swan’s lamp was that it lacked enough residual oxygen in the vacuum tube to ignite the filament, thus allowing the tungsten could glow almost white-hot without catching fire. His lamps contained the major elements seen in Edison’s lamps that October: an enclosed glass bulb from which all air had been removed, platinum lead wires, and a light-emitting element made from carbon.
Like other early inventors, Swan used a carbon rod with low electrical resistance in his lamp. Due to the relationship between resistance and current, a low resistance element required lots of current in order to become hot and glow. This meant that the conductors bringing electricity to the lamp would have to be relatively short (or impossibly thick), acceptable for an experiment or demonstration, but not for a commercial electrical system.
Joseph Swan, ca. 1880
Swan had experimented with carbonized paper filaments for some years, however. Once he learned that a high resistance filament was needed, he quickly adapted it to his own lamps and established the Swan Electric Light Company. It should be noted that Swan had been granted several patents for various lamp features before Edison’s breakthrough.
Indeed Swan’s patent position in England was strong enough that in mid-1882 a merger was arranged and the Edison & Swan United Company was formed. Known commonly as “Ediswan” the company sold lamps made with a cellulose filament that Swan had invented in 1881. Variations of the cellulose filament became an industry standard, except with the Edison Company. Edison continued using bamboo filaments until the 1892 merger that created General Electric – and that company then shifted to cellulose.
Invention of a dry photographic process
The pharmaceutical company that employed Swan, among other goods and services, produced photographic plates, which led Swan to some of his most impressive scientific innovations. In 1862, he patented the first commercially feasible procedure for carbon printing in photography. This was a method that meant that permanent photographic prints could be made. Finely divided carbon in a thin film of gelatine was sensitised with potassium chromate.
When it was placed under a negative in a frame, and exposed to light, the print could be developed. By using two kinds of gelatine, the process gave tone graduations. Drawings in sepia, red chalk or Indian ink could be reproduced by adding dyes instead of carbon. This process revolutionised photographic printing methods. The Autotype Company acquired the English rights.
Swan went on to develop another 70 inventions in this field, including, in 1877, the invention of a dry plate photographic process based on gelatine and the use of silver bromide. Then, having observed that heat increases the sensitivity of silver bromide emulsions, Swan invented the dry plate in 1871, followed by the development of bromide photographic paper in 1879.
Invention of an artificial fibers of nitro-cellulose
While searching for a better filament for his light bulb, Swan inadvertently made another advance. He developed and patented a process for squeezing nitro-cellulose through holes to form fibers. His newly established Swan Electric Company, which by merger was to become the Edison and Swan United Company, used the cellulose filaments in their bulbs. However, the textile industry also used Swan’s method to create artificial fibers for clothing and domestic products.
In July 1867, Mawson, then sheriff of Newcastle, was killed while supervising the disposal of a quantity of dumped nitroglycerin. Swan’s wife died shortly after. Swan therefore had sole responsibility for the business and his three small children. He made Mawson’s widow, his sister Elizabeth, a partner in the business, which continued as Mawson and Swan. He later remarried, even though a law to legalise second marriages had not yet been passed by Parliament. His second wife was his deceased wife’s sister. In 1883, they moved to Bromley, Kent. He later lived in Kensington in London, but moved back to the country because of heart trouble, settling in Warlingham, Surrey.
Swan added a stationery and bookselling arm to the business in Newcastle, established an extensive trade in Dutch yeast, and set up an art gallery in the city centre. He also sold scientific apparatus. As a result of his inventions, he was also in demand as a lecturer, and he took students in electricity. He took on managers to help him run the business. One was George Weddell, who ran the pharmacy business from 1891, and became a partner in 1912. Mawson, Swan and Weddell were amalgamated with Proctor, Son and Clague, and traded under the name Mawson and Proctor.
Swan was elected to the Royal Society in 1894 and was president of the Institution of Electrical Engineers from 1898 to 1899. He also served as president of the Society of Chemical Industry in 1901, the same year he was awarded an honorary doctorate degree from Durham University. In 1904, Swan was knighted, awarded the Royal Society’s Hughes Medal, and was made an honorary member of the Pharmaceutical Society. He had already received the Legion of Honour when he visited an international exhibition in Paris in 1881. The exhibition included exhibits of his inventions, and the city was lit with electric light, thanks to Swan’s invention.