1808 (first volume published) / Europe
Dalton uses atoms to explain chemical proportions
The first volume of A New System of Chemical Philosophy connects elements, atomic weights and combining proportions in a quantitative account of matter.
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The story
Dalton had discussed atomism before 1808; this date marks the first volume of his treatise. He interpreted chemical composition through combinations of atoms and estimated their relative weights. His assumptions about the simplest combinations could nevertheless produce incorrect formulas and weights: he represented water as one atom of hydrogen joined to one of oxygen. Later work on molecules, atomic structure and isotopes revised this early model.
Connections and context
Avogadro’s treatment of gases helped distinguish molecules from their constituents. The periodic table later connected atomic weights with recurring chemical properties.
Dates and precision
1808 (first volume published) Documented date
Positioned by the documented year, month or day. Missing precision is not inferred.
Representative map location
Manchester
The marker represents Dalton’s principal research setting and the first volume’s publication city, not the sole origin of atomism.
Representative coordinates · 53.4808°, -2.2426°
A marker identifies one representative place, such as a manuscript collection, laboratory or observing site. It does not mean the work happened only there, or assign a shared discovery to one country.
Bibliography
- Science History Institute: John Dalton
- Science History Institute: John Dalton and the scientific method
References are listed as plain bibliography titles. They support particular facts or context; a reference does not certify every interpretation in a story.