Daniell, John Frederic (1790-1845), an English scientist. He was born in London, and in 1831 was made professor of chemistry at King's College, London. He invented the dew-point hygrometer, which measures relative humidity; a pyrometer (a type of thermometer); and an electric cell called the Daniell cell. He wrote Meteorological Essays (1823) and other scientific works.
He is famous for a phrase he never said, for wearing turtlenecks and for hosting the original 'Cosmos' TV series. As enthusiastic about the stars as he was about marijuana, Carl Sagan led a very surprising life. Here are 10 cool facts.
He may have been born in Brooklyn, but Carl Sagan was gunning for the stars as soon as he arrived in this world. Get to know the scientist whose infectious delight in the universe still holds us spellbound.