Benjamin Franklin. Historical portrait of the American scientist and statesman Benjamin Franklin (1706-1790), at around 35 years of age. Franklin's career included journalism, science and politics. Five years after this sitting he began experiments on electrical effects which would found the science of electricity. He postulated the existence of an electrical fluid and demonstrated the electrical nature of storms. This led to the use of lightning rods to protect buildings from lightning. He suggested experiments that led to the mapping of the Gulf Stream. In 1776 he was a signatory to the American Declaration of Independence. Oil painting by R. Feke.