Joseph Swan has solved the problem of incandescent electric lighting by means of a vacuum lamp; he successfully repeats his lecture with the lamp shown in actual operation on January 17, 1879.

On February 3, 1879 he publicly demonstrates a working lamp to an audience of over seven hundred people in the lecture theater of the Literary and Philosophical Society of Newcastle upon Tyne, Sir William Armstrong presiding.

In 1879 also, Swan patents bromide paper, a type of Black and White photographic paper with pure silver bromide emulsion, which is sensitive and produces neutral black or 'cold' blue-black image tones.