"One of the great classics of chemistry in which the atomic theory is first established" (Duveen). "Dalton believed that all matter was composed of indestructible and indivisible atoms of various weights, and that these atoms remained unchanged during chemical processes. Dalton's work with relative atomic weights prompted him to construct the first periodic table of elements (in vol. I, pt. 1), to formulate laws concerning their combination and to provide schematic representations of various possible combinations of atoms. His equation of the concept of "atom" and "chemical element" was of fundamental importance, as it provided the chemist with a new and enormously fruitful model of reality" (Norman).