What do you call a number that can't keep still?
A roamin' numeral.
Sir Joseph Wilson SwanDied 27 May 1914 at age 85 (born 31 Oct 1828). English scientist, chemist, physicist and inventor, born in Sunderland, Yorkshire, who produced an early electric incandescent lamp. He began these experiments in the 1840's and obtained a UK patent covering a partial vacuum, carbon filament incandescent lamp in 1860. Swan's early lamps provided low light output, were short lived, and were operated from battery cells. Low voltage operation required relatively high filament current that necessitated that the power source be co-located near the Swan lamp. He also addressed the problem of photographic print fading and in the mid 1850s some began to experiment with a solution using carbon, perfecting and patenting the process in 1864. Thus Swan invented the dry photographic plate, an important improvement in photography.[Image: pencil drawing by M. Agnes Cohen, 1894.] |
