Pierre Perrault (1608–1680)
Encyclopedia
Pierre Perrault was a Receiver General of Finances for Paris and later a scientist who developed the concept of the hydrological cycle. He and Edme Mariotte
Edme Mariotte
Edme Mariotte was a French physicist and priest.- Biography :Edme Mariotte was the youngest son of Simon Mariotte, administrator at the district Til-Châtel , and Catherine Denisot . His parents lived in Til-Châtel and had 4 other children: Jean, Denise, Claude, and Catharine...

 were primarily responsible for making hydrology
Hydrology
Hydrology is the study of the movement, distribution, and quality of water on Earth and other planets, including the hydrologic cycle, water resources and environmental watershed sustainability...

  an experimental science.

Life

Perrault grew up in a bourgeois family, had at least seven siblings, and probably lived all his life in Paris. Little is known about his life, despite the fame of some of his younger brothers. These include Claude
Claude Perrault
Claude Perrault is best known as the architect of the eastern range of the Louvre Palace in Paris , but he also achieved success as a physician and anatomist, and as an author, who wrote treatises on physics and natural history.Perrault was born and died in Paris...

, an architect of part of the Louvre Palace; Nicholas, a doctor of theology known for his denunciation of the Jesuits; and Charles
Charles Perrault
Charles Perrault was a French author who laid the foundations for a new literary genre, the fairy tale, with his works derived from pre-existing folk tales. The best known include Le Petit Chaperon rouge , Cendrillon , Le Chat Botté and La Barbe bleue...

, author of Tales of Mother Goose.

Perrault was trained as a lawyer, and in 1654 purchased the position of Receiver General
Receiver General
A Receiver General is an officer responsible for accepting payments on behalf of a government, and for making payments to a government on behalf of other parties. Receiver General is an alternative title for a Treasurer.-See also:...

 of Finances for Paris. This post involved collecting taxes for Louis XIV, and he received a percentage of the taxes he collected. This position ruined him when Louis XIV chose to calm rebellious taxpayers by granting a remission of all taxes that were still owed after 10 years. Pierre had used some of his tax receipts for 1664 to pay creditors, and when he could not deliver the money to the royal treasury, he was forced into bankruptcy.

After the bankruptcy Perrault became an amateur scientist and focused his attention on the origin of springs
Spring (hydrosphere)
A spring—also known as a rising or resurgence—is a component of the hydrosphere. Specifically, it is any natural situation where water flows to the surface of the earth from underground...

. The result of his labor was his book de l'Origine des fontaines (On the Origin of Fountains), published anonymously in 1674 and dedicated to his friend Christian Huygens.

On the Origin of Springs

In the millennia before Perrault published his book, most natural philosophers
Natural philosophy
Natural philosophy or the philosophy of nature , is a term applied to the study of nature and the physical universe that was dominant before the development of modern science...

 asserted that there was not enough precipitation
Precipitation (meteorology)
In meteorology, precipitation In meteorology, precipitation In meteorology, precipitation (also known as one of the classes of hydrometeors, which are atmospheric water phenomena is any product of the condensation of atmospheric water vapor that falls under gravity. The main forms of precipitation...

 to account for the flow in rivers and springs. Aristotle
Aristotle
Aristotle was a Greek philosopher and polymath, a student of Plato and teacher of Alexander the Great. His writings cover many subjects, including physics, metaphysics, poetry, theater, music, logic, rhetoric, linguistics, politics, government, ethics, biology, and zoology...

 claimed that most of the water came from underground caverns in which air was transformed into water. Many others argued that seawater
Seawater
Seawater is water from a sea or ocean. On average, seawater in the world's oceans has a salinity of about 3.5% . This means that every kilogram of seawater has approximately of dissolved salts . The average density of seawater at the ocean surface is 1.025 g/ml...

 entered underground caverns, was heated until it rose as vapor, then condensed and fed springs, which in turn fed rivers. Although some philosophers such as Anaxagoras
Anaxagoras
Anaxagoras was a Pre-Socratic Greek philosopher. Born in Clazomenae in Asia Minor, Anaxagoras was the first philosopher to bring philosophy from Ionia to Athens. He attempted to give a scientific account of eclipses, meteors, rainbows, and the sun, which he described as a fiery mass larger than...

 had more realistic models of the hydrologic cycle, the weight of authority was behind the more fanciful theories.

Perrault devoted the first part of his book, On the Origin of Springs, to analyzing the ideas of his predecessors and what he called the "Common Opinion", rejecting most of it. He estimated the flow in the Seine River and compared it with rainfall in the watershed, showing that the rainfall was easily enough to account for the flow in the river. This conclusion was later supported by a more rigorous quantitative analysis published by Edme Mariotte.

With a series of experiments, Perrault showed that rain does not penetrate the soil beyond about 2 feet. Thus, most of the rain that falls does not go into springs. Perrault went on to develop the theory of the hydrologic cycle, correctly accounting for the roles of evaporation
Evaporation
Evaporation is a type of vaporization of a liquid that occurs only on the surface of a liquid. The other type of vaporization is boiling, which, instead, occurs on the entire mass of the liquid....

, transpiration
Transpiration
Transpiration is a process similar to evaporation. It is a part of the water cycle, and it is the loss of water vapor from parts of plants , especially in leaves but also in stems, flowers and roots. Leaf surfaces are dotted with openings which are collectively called stomata, and in most plants...

, throughflow
Throughflow
In hydrology, throughflow is the horizontal movement of water in the soil zone. This type of flow must first emerge on land before it enters a body of surface water to be considered throughflow...

 and surface runoff
Surface runoff
Surface runoff is the water flow that occurs when soil is infiltrated to full capacity and excess water from rain, meltwater, or other sources flows over the land. This is a major component of the water cycle. Runoff that occurs on surfaces before reaching a channel is also called a nonpoint source...

.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK