It is stimulating to see that for a time we were visited by eminent astronomers determined to achieve perfection in the definition of a universal unit of measurement, the meter. Right here near, in the top of the mountains that we see every day, a great scientific adventure was developed 200 years ago.
This past Friday, the Meridià Zero Association for the Dissemination of Science and Technology of the Marina Alta inaugurated the exhibition 'The adventure of the meter' in the exhibition hall of the Soler Blasco Museum. An exhibition that can be visited from November 3 to 30. Along with this exhibition, the covers of the 25 issues of the magazine 'Daualdeu' will also be on display.
In 1791, the Paris Academy of Sciences decided to measure an arc of the meridian that passes through the Paris Observatory to define the basic unit of length of the new measurement system, the meter. The fundamental idea was to find a unit based on nature, and defined as the thousandth spring of the quadrant of the terrestrial meridian, and that, being independent of any country or culture, would be accepted by the entire world.
Pierre François André Méchain (1744-1804) and Jean-Baptiste Joseph Delambre (1749-1822) were the astronomers chosen to carry out the relevant geodetic measurements to calculate the arc of the meridian and be able to deduce the length of the meter.
The measurement task was extended from 1792 to 1798, among other reasons due to the war between the Convention and the Kingdom of Spain due to the death of Louis XVI. These measures were carried out in a first phase between Dunkirk and Barcelona. Delambre would be in charge of making the measurements of the geodesic triangles of the northern part of the meridian from Dunkerke to Rodés (Occitania) while Méchain would make the southern part, from Rodés to Barcelona. Specifically, Méchain's last measurements were made from the Castell de Montjuic. Even so, Méchain first and the Academy later wanted to extend the geodetic measurements to the Valencian Country and Ibiza to improve precision and so that the measured meridian arc was more symmetrical with respect to the 45° parallel. So Méchain returned in a second phase to make measurements from the Desert de les Palmes in Castelló de The flat, where he tried unsuccessfully to unite Mallorca and Ibiza with geodesic triangles. The scientist died, however, of malaria in Castelló in 1804.
At the beginning of the XNUMXth century, the most prominent scientists of revolutionary France toured the highest mountains of the former Kingdom of Valencia to perform a scientific feat, measuring a meridian arc to accurately determine the length of a new unit of length, the meter. .
The exhibition covers in 16 panels the scientific adventure that united, with geodesic triangles, the Montgó mountain, between Dénia and Jávea, with Camp Vell in Ibiza. In addition, you can see numerous scientific instruments of the time donated by scientific institutions and individuals, books written by the scientists who participated in the expedition, several historical models of several ancient Valencian measures and the standard meter, among other wonders.
The northern-Catalan scientist Francesc Aragón, who explains in his memoirs (Histoire de mi jeunesse) that he met Méchain when he was measuring the meridian arc through the Rosselló, would be the one who would complete the mission in the third expedition, observing from the Cullera mountain and especially since the Montgo, finally lengthening the geodesic triangle over the sea to the Island of Ibiza and Formentera. This second phase lasted until 1808, in the middle of the French War, with all the problems for a scientist of French nationality. In 1795, France adopted the meter as its official unit of length.
The meridian measurement in Valencian lands
In addition to the presentation of the exhibition, which can be seen until November 30, the new issue of the magazine was also presented Daualdeu, which this year reached number 25. With two publications per year, the magazine has become a benchmark in the dissemination of science in the Marina Alta. Many scientists from the region and beyond have written about very diverse areas of science.
The exhibition is accompanied by interesting conferences. Pedro Duque, he will speak to us November 14th of the conquest of space as a source of science and innovation. The day November 24th, Luis García-Asenjo It will detail the geodetic work for the recovery of vestiges of the Paris meridian arc in the ancient Kingdom of Valencia.
The series of conferences was opened, after the inauguration of the exhibition, by Pep Martínez with the talk Old weights and measures. Four notes. In number 9, page 15, of Daualdeu magazine, Pep Martínez already told us something.