Dalton, John

Name:
Dalton, John
Detailed information:
(1766–1844). The first theorist since the Greek philosopher Democritus to conceive of matter in terms of small particles. The founder of the atomic theory on which all succeeding chemical investigation has been based (1807). His essential concept of the indivisibility of the atom was not called into question until 1910 when radioactive decay was established by Rutherford. Dalton's theories relating to pressures of gases and atomic combinations led to the basic generalizations stated in the law of multiple proportions, the law of constant composition, and the law of conservation of matter.See Priestly, Joseph; Chemical Laws.