Pneumatic chemistry is a term most-closely identified with an area of scientific research of the seventeenth, eighteenth, and early nineteenth centuries. Important goals of this work were an understanding of the physical properties of gases and how they relate to chemical reactions and, ultimately, the composition of matter. Several gases were isolated and identified for the first time during this period in the history of chemistry.

Investigations involving pneumatic chemistry are considered significant both for the improvements in laboratory techniques that they involved and the new information obtained about gases, including the Earth's atmosphere. However, an equal if not greater significance is the role pneumatic chemistry played in Dalton's atomic theory and, later still, in helping to understand and measure atomic and molecular masses.

Jan Baptist van Helmont

Jan Baptist van Helmont

Jan Baptist van Helmont was an early modern period Flemish chemist, physiologist, and physician. He worked during the years just after Paracelsus and iatrochemistry, and is sometimes considered to be "the founder of pneumatic chemistry"...

 (1579 – 1644) is sometimes considered the founder of pneumatic chemistry, coining the word "gas" and conducting experiments involving gases. Pneumatic chemists credited with discovering chemical elements include Joseph Priestley

Joseph Priestley

Joseph Priestley, FRS was an 18th-century English theologian, Dissenting clergyman, natural philosopher, chemist, educator, and political theorist who published over 150 works...

, Henry Cavendish

Henry Cavendish

Henry Cavendish FRS was a British scientist noted for his discovery of hydrogen or what he called "inflammable air". He described the density of inflammable air, which formed water on combustion, in a 1766 paper "On Factitious Airs". Antoine Lavoisier later reproduced Cavendish's experiment and...

, Joseph Black

Joseph Black

Joseph Black FRSE FRCPE FPSG was a Scottish physician and chemist, known for his discoveries of latent heat, specific heat, and carbon dioxide. He was professor of Medicine at University of Glasgow . James Watt, who was appointed as philosophical instrument maker at the same university...

, Daniel Rutherford

Daniel Rutherford

Daniel Rutherford was a Scottish physician, chemist and botanist who is most famous for the isolation of nitrogen in 1772.Rutherford was the uncle of the novelist Sir Walter Scott.-Early life:...

, and Carl Scheele. Other individuals who investigated gases during this period include Robert Boyle

Robert Boyle

Robert Boyle FRS was a 17th century natural philosopher, chemist, physicist, and inventor, also noted for his writings in theology. He has been variously described as English, Irish, or Anglo-Irish, his father having come to Ireland from England during the time of the English plantations of...

, Stephen Hales

Stephen Hales

Stephen Hales, FRS was an English physiologist, chemist and inventor.Hales studied the role of air and water in the maintenance of both plant and animal life. He gave accurate accounts of the movements of water in plants, and demonstrated that plants absorb air...

, Antoine Lavoisier

Antoine Lavoisier

Antoine-Laurent de Lavoisier , the "father of modern chemistry", was a French nobleman prominent in the histories of chemistry and biology...

, and John Dalton

John Dalton

John Dalton FRS was an English chemist, meteorologist and physicist. He is best known for his pioneering work in the development of modern atomic theory, and his research into colour blindness .-Early life:John Dalton was born into a Quaker family at Eaglesfield, near Cockermouth, Cumberland,...

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