In 1803, John Dalton's atomic theory brought them into scientific ... discovered the electron, proving that the atom had smaller constituent parts. That opened the door to subatomic hypotheses ...

There was little change in the understanding of the atom until John Dalton (1766-1844), an English chemist, concluded that: all matter is made of atoms, and atoms are indestructible and cannot be ...

The scientist John Dalton carried out a series of experiments. He concluded that all matter was made of tiny particles called atoms. He suggested that an atom was a tiny solid ball. He published ...