Dalton, John

Dalton, John (dôl`tən), 1766–1844, English scientist. He revived the atomic theory (see atom), which he formulated in the first volume of his New System of Chemical Philosophy (2 vol., 1808–27). He had already applied the concept to a table of atomic weights (1803), in a paper (1805) on the absorption of gases, and in developing his famous law of partial pressures, known also as Dalton's law. His interest in weather conditions led him to keep daily records from 1787 and to write Meteorological Observations and Essays (1793). Dalton, himself afflicted with color blindness, investigated (c.1794) the condition, known also as Daltonism. From 1793 he taught mathematics and physical sciences at New College, Manchester. He was a member of the Royal Society (from 1822) and in 1825 received its medal for his work on the atomic theory.

Bibliography

See study by A. Thackray (1972).

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Dalton, John

John Dalton, detail of an engraving by W. Worthington, after a portrait by William Allen, 1814.

(credit: Courtesy of the trustees of the British Museum; photograph, J.R. Freeman & Co. Ltd.)

(born Sept. 5 or 6, 1766, Eaglesfield, Cumberland, Eng.—died July 27, 1844, Manchester) British chemist and physicist. He spent most of his life in private teaching and research. His work on gases led him to state Dalton's law (see gas laws). He devised a system of chemical symbols, ascertained the relative weights of atoms, and arranged them into a table. His masterpiece of synthesis was the atomic theory—the theory that each element is composed of tiny, indestructible particles called atoms that are all alike and have the same atomic weight—which elevated chemistry to a quantitative science. He was also the first to describe colour blindness (1794), and his lifelong meteorological journal contains more than 200,000 observations. He is remembered as one of the fathers of modern physical science.

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Dalton, John 

Born Sept. 6, 1766, in Eaglesfield, England; died July 27, 1844, in Manchester. English physicist and chemist. Member of the Royal Society of London (1822).

The son of a weaver, Dalton, who was self-educated, taught mathematics in Kendal and Manchester. He was a member (from 1794), secretary (from 1800), and chairman (from 1817) of the Manchester Literary and Philosophical Society. While studying the properties of gas mixtures, he discovered the law of partial gas pressures (1801) and the dependence of the dissolution of gases on their partial pressures (1803). He investigated the dependence of the evaporation of a liquid on pressure, temperature, and other factors. In 1802 he established (somewhat ahead of J. Gay-Lussac and independently of J. Charles) that at constant pressure all gases expand identically when temperature is increased identically. Dalton wrote fundamental works on chemical atomics. In 1794 he was the first to describe a visual defect (from which he himself suffered) that came to be called Daltonism (color blindness).

WORKS

Sbornik izbrannykh rabot po atomistike. Leningrad. 1940. (Translated from English. 1802–10.)

REFERENCES

Kedrov, B.M. Atomistika Dal’tona. Moscow-Leningrad. 1949.
Henry. W. C. Memoirs of the Life and Scientific Researches of John Dalton. London, 1854.
Smith, R. Memoirs of John Dalton and History of the Atomic Theory up to His Time. London, 1956.