Dieudonné Sylvain Guy Tancrède de Dolomieu usually known as Déodat de Dolomieu (Dolomieu, Isère

Dolomieu, Isère

Dolomieu is a commune in the Isère department in south-eastern France.-Notable resident:Mathematician Élie Joseph Cartan was born here in 1869.Also geologist Déodat Gratet de Dolomieu was born here in 1750.-See also:*Communes of the Isère department...

, June 23, 1750 - Chateauneuf

Châteauneuf, Saône-et-Loire

Châteauneuf is a commune in the Saône-et-Loire department in the region of Bourgogne in eastern France.-References:*...

November 28, 1801) was a French geologist

Geologist

A geologist is a scientist who studies the solid and liquid matter that constitutes the Earth as well as the processes and history that has shaped it. Geologists usually engage in studying geology. Geologists, studying more of an applied science than a theoretical one, must approach Geology using...

; the rock dolomite

Dolomite

Dolomite is a carbonate mineral composed of calcium magnesium carbonate CaMg2. The term is also used to describe the sedimentary carbonate rock dolostone....

 and the largest summital crater on the Piton de la Fournaise

Piton de la Fournaise

Piton de la Fournaise : "Peak of the Furnace" is a shield volcano on the eastern side of Réunion island in the Indian Ocean. It is currently one of the most active volcanoes in the world, along with Kīlauea in the Hawaiian Islands , Stromboli, Etna and Mount Erebus in Antarctica...

 volcano were named after him.

Déodat de Dolomieu was born in Dauphiné

Dauphiné

The Dauphiné or Dauphiné Viennois is a former province in southeastern France, whose area roughly corresponded to that of the present departments of :Isère, :Drôme, and :Hautes-Alpes....

, France

France

The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

, one of 11 children of the Marquis de Dolomieu and his wife Marie-Françoise de Berénger. As a child young Déodat showed considerable intellectual potential and special interest in the natural surroundings of his home in the Alps

Alps

The Alps is one of the great mountain range systems of Europe, stretching from Austria and Slovenia in the east through Italy, Switzerland, Liechtenstein and Germany to France in the west....

 of southeastern France. Dolomieu began his military career with the Sovereign and Military Order of the Knights of Saint John (also called the Knights Hospitaller

Knights Hospitaller

The Sovereign Military Hospitaller Order of Saint John of Jerusalem of Rhodes and of Malta , also known as the Sovereign Military Order of Malta , Order of Malta or Knights of Malta, is a Roman Catholic lay religious order, traditionally of military, chivalrous, noble nature. It is the world's...

 or the Knights of Malta) at the age of 12. His association with the Maltese Order caused him difficulties throughout his life, beginning with a duel, which he fought at the age of 18, where he killed a fellow member of the order. For this infraction he was sentenced to life in prison but due to the intercession of Pope Clement XIII

Pope Clement XIII

Pope Clement XIII , born Carlo della Torre di Rezzonico, was Pope from 16 July 1758 to 2 February 1769....

 he was released after 1 year.

During the period prior to the French Revolution

French Revolution

The French Revolution , sometimes distinguished as the 'Great French Revolution' , was a period of radical social and political upheaval in France and Europe. The absolute monarchy that had ruled France for centuries collapsed in three years...

 Dolomieu took full part in the intellectual ferment of France and the rest of Europe. He maintained numerous social contacts among the nobility and although he never married, Dolomieu had something of a reputation as a ladies' man. Through his friend and mentor, the Duke de La Rochefoucauld, Dolomieu was made a corresponding member of the Royal Academy of Sciences. He spent his spare time taking scientific excursions throughout Europe collecting mineral specimens and visiting mining areas. His particular interests included mineralogy

Mineralogy

Mineralogy is the study of chemistry, crystal structure, and physical properties of minerals. Specific studies within mineralogy include the processes of mineral origin and formation, classification of minerals, their geographical distribution, as well as their utilization.-History:Early writing...

, volcanology

Volcanology

Volcanology is the study of volcanoes, lava, magma, and related geological, geophysical and geochemical phenomena. The term volcanology is derived from the Latin word vulcan. Vulcan was the ancient Roman god of fire....

, and the origin of mountain ranges. Although Dolomieu was greatly interested in volcanos, he became convinced that water played a major role in shaping the surface of the Earth through a series of prehistoric, catastrophic events. Dolomieu was not a uniformitarian geologist. His contemporary, James Hutton

James Hutton

James Hutton was a Scottish physician, geologist, naturalist, chemical manufacturer and experimental agriculturalist. He is considered the father of modern geology...

, did not publish the principle of uniformitarianism

Uniformitarianism (science)

In the philosophy of naturalism, the uniformitarianism assumption is that the same natural laws and processes that operate in the universe now, have always operated in the universe in the past and apply everywhere in the universe. It has included the gradualistic concept that "the present is the...

 until 1795. Dolomieu was an observationalist and spent much time collecting and categorizing geological data. Unlike Hutton, no scientific principles or theories are credited to him, although he left his permanent mark on geology in another way.

During one of his field trips to the Alps

Alps

The Alps is one of the great mountain range systems of Europe, stretching from Austria and Slovenia in the east through Italy, Switzerland, Liechtenstein and Germany to France in the west....

 of Tyrol

County of Tyrol

The County of Tyrol, Princely County from 1504, was a State of the Holy Roman Empire, from 1814 a province of the Austrian Empire and from 1867 a Cisleithanian crown land of Austria-Hungary...

 (today part of northeastern Italy) Dolomieu discovered a calcareous rock which, unlike limestone

Limestone

Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....

, did not effervesce in weak acid. He published these observations in 1791 in the Journal de Physique. The following year, in the same journal, the rock was named dolomie (or dolomite

Dolomite

Dolomite is a carbonate mineral composed of calcium magnesium carbonate CaMg2. The term is also used to describe the sedimentary carbonate rock dolostone....

, in English) by Nicolas-Théodore de Saussure

Nicolas-Théodore de Saussure

Nicolas-Théodore de Saussure was a Swiss chemist and student of plant physiology who made seminal advances in phytochemistry....

. Today both the rock and its major mineral constituent bear the name of Dolomieu, as do the Dolomites

Dolomites

The Dolomites are a mountain range located in north-eastern Italy. It is a part of Southern Limestone Alps and extends from the River Adige in the west to the Piave Valley in the east. The northern and southern borders are defined by the Puster Valley and the Sugana Valley...

, the mountain range in northwestern Italy, where he first identified the rock.

In addition to his scientific activities Dolomieu continued to advance in rank in the Knights of Malta and was promoted to Commander in 1780. However, he continued to have difficulties as a result of his liberal political leanings which were unpopular among the conservative nobility who controlled the Order. Dolomieu retired from active military service in 1780 to devote full time to his travels and scientific work.

Dolomieu was at first a strong partisan of the French Revolution

French Revolution

The French Revolution , sometimes distinguished as the 'Great French Revolution' , was a period of radical social and political upheaval in France and Europe. The absolute monarchy that had ruled France for centuries collapsed in three years...

, which began in 1789. However, the murder, of his friend the Duc de la Rochefoucauld, a close brush (shave?) with the guillotine

Guillotine

The guillotine is a device used for carrying out :executions by decapitation. It consists of a tall upright frame from which an angled blade is suspended. This blade is raised with a rope and then allowed to drop, severing the head from the body...

, and the beheading of several of his relatives, turned him against the revolution. During this time Dolomieu became a supporter of Napoleon Bonaparte. In 1795, having lost his fortune in the revolution, Dolomieu accepted the position of Professor of Natural Sciences at the École Centrale Paris

École Centrale Paris

École Centrale Paris is a French university-level institution in the field of engineering. It is also known by its original name École centrale des arts et manufactures, or ECP. Founded in 1829, it is one of the oldest and most prestigious engineering schools in France and has the special status...

 and contracted to write the mineralogical portion of the Encyclopédie Méthodique

Encyclopédie Méthodique

The Encyclopédie méthodique par ordre des matières is a roughly 210 to 216 volumes encyclopedia that was published between 1782 and 1832 by the French publisher Charles Joseph Panckoucke, his son-in-law Henri Agasse, and the latter´s wife, Thérèse-Charlotte Agasse...

. The following year he was appointed Inspector of Mines and Professor at the École nationale supérieure des mines de Paris

École nationale supérieure des mines de Paris

The École Nationale Supérieure des Mines de Paris was created in 1783 by King Louis XVI in order to train intelligent directors of mines. It is one of the most prominent French engineering schoolsThe École Nationale Supérieure des Mines de Paris (also known as Mines ParisTech, École des Mines de...

, where his portrait still hangs in the library. His extensive mineral collection is today housed at the Muséum National d'Histoire Naturelle

Muséum national d'histoire naturelle

The Muséum national d'Histoire naturelle is the National Museum of Natural History in Paris, France.- History :The museum was formally founded on 10 June 1793, during the French Revolution...

 de Paris.

By 1798 Dolomieu had developed an international reputation as one of the leading geologists in the world and was invited to join the scientific expedition accompanying Bonaparte's invasion of Egypt, as part of the natural history and physics section of the Institut d'Égypte

Institut d'Égypte

The Institut d’Égypte was a learned academy formed by Napoleon Bonaparte to carry out research during his Egyptian campaign.-Early work:It first met on 24 August 1798, with Gaspard Monge as president, Bonaparte himself as vice-president and Joseph Fourier and Costaz as secretaries...

. In March of 1799 Dolomieu became ill and was forced to leave Alexandria, Egypt for France. His ship, caught in a storm, sought refuge at the port of Taranto

Taranto

Taranto is a coastal city in Apulia, Southern Italy. It is the capital of the Province of Taranto and is an important commercial port as well as the main Italian naval base....

, Italy where Dolomieu was made a prisoner of war. The city was part of the Kingdom of the Two Sicilies

Kingdom of the Two Sicilies

The Kingdom of the Two Sicilies, commonly known as the Two Sicilies even before formally coming into being, was the largest and wealthiest of the Italian states before Italian unification...

, which was then at war with France. Dolomieu had previously made a powerful enemy of the Grand Master of the Maltase Order when he helped negotiate the surrender of the island of Malta to Napoleon. The Grand Master denounced Dolomieu and he was transferred to Messina, Sicily and imprisoned under horrible conditions, in solitary confinement, for the next 21 months.

The imprisonment of a world-famous scientist, under such conditions, was abhorrent to the intellectual community of Europe. Even the scientific community of England (who was at war with France) protested the confinement. Talleyrand, the French foreign minister, attempted to negotiate Dolomieu's release through the Pope. Napoleon, who was First Consul of France at the time, felt that asking for such an intervention by the Pope would be dishonorable. The future Emperor's approach to the problem was more direct. In the spring of 1800 Napoleon lead the French army into Italy, delivering a crushing blow to the Austrians and their Italian allies on June 14, at the Battle of Marengo. All of Italy then came within Napoleon's sphere. One of the terms dictated by Napoleon in the peace treaty of Florence (March 1801) was the immediate release of Dolomieu.

Upon his liberation Dolomieu resumed his scientific studies and field excursions. But his health, broken by the long imprisonment in Sicily, gave way during a trip to the Alps. Déodat de Dolomieu died on November 28, 1801 at the home of his sister at Châteauneuf, not far from his boyhood home in Dauphiné.

Dr. George F. Kunz wrote about his contributions to mineralogy. and