Why was John Dalton considered the father of atomic theory?
Atomic theory In 1800 he became a secretary of the Manchester Literary and Philosophical Society, and in the following year he orally presented an important series of papers, entitled “Experimental Essays” on the constitution of mixed gases; on the pressure of steam and other vapours at different temperatures, both in a vacuum and in air; on evaporation; and on the thermal expansion of gases. These four essays were published in the Memoirs of the Lit & Phil in 1802. The second of these essays opens with the striking remark, There can scarcely be a doubt entertained respecting the reducibility of all elastic fluids of whatever kind, into liquids; and we ought not to despair of affecting it in low temperatures and by strong pressures exerted upon the unmixed gases further. After describing experiments to ascertain the pressure of steam at various points between 0° and 100°C (32° and 212°F), he concluded from observations on the vapour pressure of six different liquids, that the variation
