During that time, Fahrenheit met or was in contact with Ole Rømer, Christian Wolff, and Gottfried Leibniz.

According to a letter Fahrenheit wrote to his friend Herman Boerhaave, his scale was built on the work of Ole Rømer, whom he had met earlier.

It is for this reason that normal human body temperature is approximately 98 ° ( oral temperature ) on the revised scale ( whereas it was 90 ° on Fahrenheit's multiplication of Rømer, and 96 ° on his original scale ).

The Danish and German geographical mile ( geografisk mil and geographische Meile or geographische Landmeile, respectively ) is 4 minutes of arc, and was defined as approximately 7421. 5 metres by the astronomer Ole Rømer of Denmark.

An early experiment to measure the speed of light was conducted by Ole Rømer, a Danish physicist, in 1676.

Ole Christensen Rømer (; 25 September 1644, Århus – 19 September 1710, Copenhagen ) was a Danish astronomer who in 1676 made the first quantitative measurements of the speed of light.

Rømer was born on 25 September 1644 in Århus to a merchant and skipper, Christen Pedersen, and Anna Olufsdatter Storm, daughter of an alderman.

Christen Pedersen had taken to using the name Rømer, which means that he was from the Danish island of Rømø, to distinguish himself from a couple of other people named Christen Pedersen.

There are few sources on Ole Rømer until his immatriculation in 1662 at the University of Copenhagen, at which his mentor was Rasmus Bartholin who published his discovery of the double refraction of a light ray by Iceland spar ( calcite ) in 1668, while Rømer was living in his home.

Rømer was given every opportunity to learn mathematics and astronomy using Tycho Brahe's astronomical observations, as Bartholin had been given the task of preparing them for publication.

In 1681, Rømer returned to Denmark and was appointed professor of astronomy at the University of Copenhagen, and the same year he married Anne Marie Bartholin, the daughter of Rasmus Bartholin.

In 1705, Rømer was made the second Chief of the Copenhagen Police, a position he kept until his death in 1710.

In Copenhagen, Rømer made rules for building new houses, got the city's water supply and sewers back in order, ensured that the city's fire department got new and better equipment, and was the moving force behind the planning and making of new pavement in the streets and on the city squares.

Rømer presented his results to the French Academy of Sciences, and it was summarised soon after by an anonymous reporter in a short paper,, published 7 December 1676 in the Journal des sçavans.

The Rundetårn ( round tower ) was used in the 17th century as an observatory by Ole Rømer.

The effect of the finite speed of light on observations of celestial objects was first recognised by Ole Rømer in 1675, during a series of observations of eclipses of the moons of Jupiter.

Rømer then saw that the freezing point of pure water was roughly one eighth of the way ( about 7. 5 degrees ) between these two points, so he redefined the lower fixed point to be the freezing point of water at precisely 7. 5 degrees.

Picard collaborated and corresponded with many scientists, including Isaac Newton, Christiaan Huygens, Ole Rømer, Rasmus Bartholin, Johann Hudde, and even his main competitor, Giovanni Cassini, although Cassini was often less than willing to return the gesture.

The family's most prominent member was Nils Henriksson ( died 1523 ), Lord High Steward of Norway, who was married with the famed lady Ingegjerd Ottesdotter Rømer, heiress of Austrått.

# In Touch-Starting from an attempt for cheaper fusion power using superconductivity, which was discovered by Onnes, with liquid gas provided by Louis-Paul Cailletet, who carried out experiments on a tower built by Gustave Eiffel, who also built the Statue of Liberty with its famous poem by the Jewish activist Emma Lazarus, helped by Oliphant, whose boss Elgin was the son of the man who stole the Elgin Marbles and sold them with the help of royal painter Thomas Lawrence, whose colleague Dr. Hunter had an assistant whose wife's lodger was Benjamin Franklin, who charted the Gulf Stream with a thermometer Fahrenheit borrowed from Ole Rømer, whose friend Picard surveyed Versailles and provided the water for the fountains and the royal gardens and all the trees that inspired Duhamel to write the book on gardening that was read by the architect William Chambers, who hired the Scottish stonemason Thomas Telford, whose idea for London Bridge was turned down by Thomas Young, whose light waves travel in ether, as do Hertz's electricity waves, with which Helmholtz prods a frog to disprove the vitalists, whose leader, Klages, analyzes handwriting so individual zip codes have to be capital letters to get your mail to a jungle village to keep you " In Touch ".

Oddly, Cassini seems to have abandoned this reasoning, which Rømer adopted and set about buttressing in an irrefutable manner, using a selected number of observations performed by Picard and himself between 1671 and 1677.

Rømer observed immersions in C from the symmetric positions F and G, to avoid confusing eclipses ( Io shadowed by Jupiter from C to D ) and occultations ( Io hidden behind Jupiter at various angles ).

Although the king had been persuaded by Ole Rømer to introduce the Gregorian calendar in Denmark-Norway in 1700, the astronomer's observations and calculations were among the treasures lost to the fire.

The brilliant contributions to atomic physics of Niels Bohr ( 1885 – 1962 ), the contributions to linguistics by Otto Jespersen ( 1860 – 1943 ), Ludwig A. Colding's ( 1815 – 1888 ) neglected articulation of the principle of conservation of energy, the pioneering work in anatomy and geology by Nicolas Steno ( 1638 – 1686 ), and the astronomical discoveries of Tycho Brahe ( 1546 – 1601 ) and Ole Rømer ( 1644-1710 ) indicate the range of Danish scientific achievement.

* Danish astronomer Ole Rømer measures the speed of light by observing the eclipses of Jupiter's moons, obtaining a speed of 140, 000 miles per second ( approximately 25 % too slow ).

Ordinary cycloids were studied by Galileo Galilei and Marin Mersenne as early as 1599 but cycloidal curves were first conceived by Ole Rømer in 1674 while studying the best form for gear teeth.

* the Ole Rømer Medal, awarded by the president of the University of Copenhagen, 2001 ;

The development of today's thermometers and temperature scales began in the early 18th century, when Gabriel Fahrenheit adapted a thermometer using mercury and a scale both developed by Ole Christensen Rømer.

Rømer later discovered that differing standards for the Rhine foot existed, and in 1698 an iron Copenhagen standard was made.

Fahrenheit visited him in 1708 and improved on the Rømer scale, the result being the familiar Fahrenheit temperature scale still in use today in a few countries.

In 1700, Rømer managed to get the king to introduce the Gregorian calendar in Denmark-Norway — something Tycho Brahe had argued for in vain a hundred years earlier.

The symbol for degrees Rankine is ° R ( or ° Ra if necessary to distinguish it from the Rømer and Réaumur scales ).

( Rømer scale ), The temperature scale used for his thermometer had 0 representing the temperature of a salt and ice mixture ( at about 259 K ).

* 1676 – Ole Rømer measures the speed of light for the first time

Ole Rømer headed the preparatory work for the rebuilding of Amalienborg in the early 1690s.

A pendulum definition for the foot was first suggested by Rømer, introduced in 1820, and changed in 1835.

Rømer also developed one of the first temperature scales.

Rømer also established several navigation schools in many Danish cities.

Poincaré went on to note that Rømer also had to assume that Jupiter's moons obey Newton's laws, including the law of gravitation, whereas it would be possible to reconcile a different speed of light with the same observations if we assumed some different ( probably more complicated ) laws of motion.

Ole Rømer at work

Assume the Earth is in L, at the second quadrature with Jupiter ( i. e. ALB is 90 °), and Io emerges from D. After several orbits of Io, at 42. 5 hours per orbit, the Earth is in K. Rømer reasoned that if light is not propagated instantaneously, the additional time it takes to reach K, that he reckoned about 3½ minutes, would explain the observed delay.