Joseph Wilson Swan was born in 1828. 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.

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.

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.

Sir Joseph Swan died in 1914, aged 86.

Photography

Swan's first major invention was the Carbon process in 1864. 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.

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.