Atom to the positively charged nucleus by the attraction created from opposite electric charges. If an atom has more or fewer electrons than its atomic number, then it becomes respectively negatively or positively charged as a whole; a charged atom is called an ion. Electrons have been known since the late 19th century, mostly thanks to J.J. Thomson; see history of subatomic physics for details. Protons have a positive charge and a mass 1,836 times that of the electron, at . The number of protons in an atom is called its atomic number. Ernest Rutherford (1919) observed that nitrogen under alpha-particle
The History and Adventures of an Atom idea of atoms, the ideas of Democritus—though, of course, he is also being satirical. The book was published anonymously in 1769. Smollett's authorship of the book has been disputed, but it is generally included and discussed among his works. Writing in 1821, Sir Walter Scott wrote, "The chief purpose of the work (besides that of giving the author the opportunity to raise his hand, like that of Ishmael, against every man) is to inspire a national horror of continental connexions." The History and Adventures of an Atom The History and Adventures of an Atom, by Tobias Smollett, is a novel