Roger Bacon was an English philosopher and Franciscan friar who placed considerable emphasis on the study of nature through empirical methods. He is sometimes credited (mainly since the nineteenth century) as one of the earliest European ad...

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". Va...

The Honourable Robert Boyle was an Irish natural philosopher, noted for his work in physics and chemistry. He was an alchemist; and believing the transmutation of metals to be a possibility, he carried out experiments in the hope of effect...

Robert Hooke, natural philosopher, inventor, architect, chemist, mathematician, physicist, engineer. Robert Hooke is one of the most neglected natural philosophers of all time. The inventor of, amongst other things, the iris diaphragm in ca...

Daniel Gabriel Fahrenheit, German physicist and instrument maker. He spent most of his life in the Netherlands, where he devoted himself to the study of physics and the manufacture of precision meteorological instruments. He is best known f...

Joseph Black 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 (where he also served as lecturer in Chemistry). James Wat...

Henry Cavendish 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 La...

Joseph Priestley was an 18th-century English theologian, Dissenting clergyman, natural philosopher, educator, and political theorist who published over 150 works. He is usually credited with the discovery of oxygen, having isolated it in it...

James Watt was a Scottish inventor and mechanical engineer whose improvements to the Newcomen steam engine were fundamental to the changes brought by the Industrial Revolution in both his native Great Britain and the rest of the world. W...

Antoine-Laurent de Lavoisier was a French nobleman and chemist central to the 18th-century Chemical Revolution and a large influence on both the histories of chemistry and biology. He is widely considered to be the "Father of Modern Chemist...

Joseph Louis Proust was a French chemist. Proust’s largest accomplishment into the realm of science was disproving Berthollet with the law of definite proportions, which is sometimes also known as Proust's Law. Proust studied copper carbona...

John Dalton 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. He developed the first useful atomic theory of...

Among the young men whom Antoine-Laurent Lavoisier deeply influenced was Eleuthère Irénée du Pont (1771–1834), the founder of the DuPont Company. His father, Pierre Samuel du Pont—an economist, government official, and publicist—was among t...

In 1811 Amedeo Avogadro hypothesized that equal volumes of gases at the same temperature and pressure contain equal numbers of molecules. From this hypothesis it followed that relative molecular weights of any two gases are the same as the...

Sir Humphry Davy, 1st Baronet FRS MRIA was a British chemist and inventor. He is probably best remembered today for his discoveries of several alkali and alkaline earth metals, as well as contributions to the discoveries of the elemental n...