Jean-Étienne Guettard (22 September 1715 – 7 January 1786), French naturalist and

mineralogist Mineralogy is a subject of geology specializing in the scientific study of the chemistry, crystal structure, and physical (including optical) properties of minerals and mineralized artifacts. Specific studies within mineralogy include the proce ...

, was born at

Étampes Étampes () is a commune in the metropolitan area of Paris, France. It is located south-southwest from the center of Paris (as the crow flies). Étampes is a sub-prefecture of the Essonne department. Étampes, together with the neighboring ...

, near Paris. In boyhood, he gained a knowledge of

plant Plants are predominantly photosynthetic eukaryotes of the kingdom Plantae. Historically, the plant kingdom encompassed all living things that were not animals, and included algae and fungi; however, all current definitions of Plantae exclu ...

s from his grandfather, who was an

apothecary ''Apothecary'' () is a mostly archaic term for a medical professional who formulates and dispenses '' materia medica'' (medicine) to physicians, surgeons, and patients. The modern chemist (British English) or pharmacist (British and North Amer ...

, and later he qualified as a

doctor in medicine Doctor of Medicine (abbreviated M.D., from the Latin ''Medicinae Doctor'') is a medical degree, the meaning of which varies between different jurisdictions. In the United States, and some other countries, the M.D. denotes a professional degree. T ...

. Pursuing the study of

botany Botany, also called , plant biology or phytology, is the science of plant life and a branch of biology. A botanist, plant scientist or phytologist is a scientist who specialises in this field. The term "botany" comes from the Ancient Greek w ...

in various parts of

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan area ...

and other countries, he began to take notice of the relation between the distribution of plants and the

soil Soil, also commonly referred to as earth or dirt Dirt is an unclean matter, especially when in contact with a person's clothes, skin, or possessions. In such cases, they are said to become dirty. Common types of dirt include: * Debri ...

s and subsoils. In this way his attention came to be directed to

mineral In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2 ...

s and

rocks In geology, rock (or stone) is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its chemical composition, and the way in which it is formed. Rocks form the Earth's ...

. In 1746, he communicated to the

Academy of Sciences An academy of sciences is a type of learned society or academy (as special scientific institution) dedicated to sciences that may or may not be state funded. Some state funded academies are tuned into national or royal (in case of the Unit ...

Paris Paris () is the Capital city, capital and List of communes in France with over 20,000 inhabitants, most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), ma ...

a memoir on the distribution of minerals and rocks, and this was accompanied by a

map A map is a symbolic depiction emphasizing relationships between elements of some space, such as objects, regions, or themes. Many maps are static, fixed to paper or some other durable medium, while others are dynamic or interactive. Although ...

on which he had recorded his observations. He thus, as remarked by W. D. Conybeare, "first carried into execution the idea, proposed by

Martin Lister Martin Lister FRS (12 April 1639 – 2 February 1712) was an English naturalist and physician. His daughters Anne and Susanna were two of his illustrators and engravers. J. D. Woodley, ‘Lister , Susanna (bap. 1670, d. 1738)’, Oxford Dic ...

years before, of

geological Geology () is a branch of natural science concerned with Earth and other astronomical objects, the features or rocks of which it is composed, and the processes by which they change over time. Modern geology significantly overlaps all other E ...

maps." In the course of his journeys he made a large collection of

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

s and figured many of them, but he had no clear ideas about the sequence of strata. He made observations also on the

degradation Degradation may refer to: Science * Degradation (geology), lowering of a fluvial surface by erosion * Degradation (telecommunications), of an electronic signal * Biodegradation of organic substances by living organisms * Environmental degradatio ...

of mountains by rain, rivers and sea; and he was the first to ascertain the existence of former

volcano A volcano is a rupture in the Crust (geology), crust of a Planet#Planetary-mass objects, planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and volcanic gas, gases to escape from a magma chamber below the surface. On Ear ...

es in the district of

Auvergne Auvergne (; ; oc, label= Occitan, Auvèrnhe or ) is a former administrative region in central France, comprising the four departments of Allier, Puy-de-Dôme, Cantal and Haute-Loire. Since 1 January 2016, it has been part of the new region Au ...

. In 1759, Guettard was elected a foreign member of the Royal Swedish Academy of Sciences. He died in Paris on 7 January 1786. His publications include: * ''Observations sur les plantes'' (2 vols, 1747) * ''Histoire de la découverte faite en France de matières semblables à celles dont la porcelaine de la Chine est composée'' (1765) * ''Mémoires sur différentes parties des sciences et arts'' (5 vols, 1768–1783) * ''Mémoires sur la minéralogie du Dauphiné'' (2 vols, 1779).
''Atlas et description minéralogiques de la France'' (1780)

"Atlas minéralogique de la France, volume de planches" (1780)
See ''The Founders of Geology'', by Sir A Geikie (1897).

References

* {{DEFAULTSORT:Guettard, Jean-Etienne 1715 births 1786 deaths People from Étampes French naturalists French mineralogists Members of the French Academy of Sciences Members of the Royal Swedish Academy of Sciences 18th-century French physicians

See also

References