Editing Metrication (section)

===Spain (1700–1889)===
[[File:General Carlos Ibáñez e Ibáñez de Ibero.jpg|thumb|upright=0.75|Don Carlos Ibáñez e Ibáñez de Ibero, first president of the [[International Association of Geodesy|International Geodetic Association]] and of the [[General Conference on Weights and Measures|International Committee for Weights and Measures]]|left]]
Until the ascent of the [[House of Bourbon|Bourbon]] monarchy in Spain in 1700, each region of Spain had its own system of measurement. The new Bourbon monarchy tried to centralise control and with it the system of measurement. There were debates regarding the desirability of retaining the [[Kingdom of Castile|Castilian]] units of measure or, in the interests of harmonisation, adopting the French system.<ref name="metricSpain">{{cite web
|url = http://www.2iceshs.cyfronet.pl/2ICESHS_Proceedings/Chapter_16/R-8_Navarro_Merino.pdf
|title = The units of length in the Spanish treatises of military engineering
|first1 = Juan Navarro
|last1 = Loidi
|first2 = Pilar Merino
|last2 = Saenz
|work = The Global and the Local: The History of Science and the Cultural Integration of Europe. Proceedings of the 2nd ICESHS
|location = Cracow, Poland
|date = 6–9 September 2006
|publisher = The Press of the Polish Academy of Arts and Sciences
|access-date = 17 March 2011
|archive-date = 3 October 2011
|archive-url = https://web.archive.org/web/20111003220229/http://www.2iceshs.cyfronet.pl/2ICESHS_Proceedings/Chapter_16/R-8_Navarro_Merino.pdf
|url-status = dead
}}</ref> Although Spain assisted [[Pierre Méchain|Méchain]] in his meridian survey, the Government feared the French revolutionary movement and reinforced the Castilian units of measure to counter such movements. By 1849 however, it proved difficult to maintain the old system and in that year the metric system became the legal system of measure in Spain.<ref name = metricSpain/>

The [[Spanish Royal Academy of Sciences|Spanish Royal Academy of Science]] urged the Government to approve the creation of a large-scale map of [[Spain]] in 1852. The following year [[Carlos Ibáñez e Ibáñez de Ibero]] was appointed to undertake this task. All the scientific and technical material had to be created. Ibáñez e Ibáñez de Ibero and Saavedra went to [[Paris]] to supervise the production by Brunner of a measuring instrument which they had devised and which they later compared with [[Jean-Charles de Borda|Borda]]'s double-toise N°1 which was the main reference for measuring all geodetic bases in France and whose length was by definition 3.8980732 metres at a specified temperature.<ref name=":2" /><ref>{{Cite book|last1=Delambre|first1=Jean-Baptiste (1749-1822) Auteur du texte|url=https://gallica.bnf.fr/ark:/12148/bpt6k1106055|title=Base du système métrique décimal, ou Mesure de l'arc du méridien compris entre les parallèles de Dunkerque et Barcelone. T. 3 /, exécutée en 1792 et années suivantes, par MM. Méchain et Delambre, rédigée par M. Delambre,...|last2=Méchain|first2=Pierre (1744-1804) Auteur du texte|date=1806–1810|publisher=|isbn=|location=|pages=139, 228|access-date=5 January 2021|archive-date=9 January 2021|archive-url=https://web.archive.org/web/20210109172924/https://gallica.bnf.fr/ark:/12148/bpt6k1106055|url-status=live}}</ref>

In 1865 the triangulation of [[Spain]] was connected with that of [[Portugal]] and [[France]]. In 1866 at the conference of the Association of Geodesy in [[Neuchâtel]], Ibáñez announced that [[Spain]] would collaborate in remeasuring the [[Paris meridian|French meridian arc]]. In 1879 Ibáñez and [[François Perrier (French Army officer)|François Perrier]] (representing France) completed the junction between the geodetic network of Spain and [[French Algeria|Algeria]] and thus completed the measurement of the [[Paris meridian|French meridian arc]] which extended from [[Shetland]] to the [[Sahara]].

In 1866, Spain and Portugal joined the Central European Arc Measurement which would become the [[International Association of Geodesy|European Arc Measurement]] the next year. In 1867 at the second general conference of the geodetic association held in Berlin, the question of an international standard unit of length was discussed in order to combine the measurements made in different countries to determine the size and shape of the Earth. The conference proposed according to recommendations drawn up by a committee chaired by [[Otto Wilhelm von Struve]] director of the [[Pulkovo Observatory]] in St. Petersburg the adoption of the [[metre]] and the creation of an international metre commission, after a preliminary discussion held in Neuchâtel between [[Johann Jacob Baeyer]] director of the Royal Prussian Geodetic Institute, [[Adolphe Hirsch]] founder of the [[Neuchâtel Observatory]] and [[Carlos Ibáñez e Ibáñez de Ibero]] Spanish representative, founder and first director of the [[Instituto Geográfico Nacional (Spain)|Instituto Geográfico Nacional]].<ref>{{Cite book|last=|first=|url=http://gfzpublic.gfz-potsdam.de/pubman/item/escidoc:108187:4/component/escidoc:272449/Generalbericht.mitteleurop%C3%A4ische.Gradmessung%201867.pdf|title=Bericht über die Verhandlungen der vom 30. September bis 7. October 1867 zu BERLIN abgehaltenen allgemeinen Conferenz der Europäischen Gradmessung.|publisher=Central Bureau der Europäischer Gradmessung|year=1868|isbn=|location=Berlin|pages=14. 123–134}}</ref><ref>{{cite journal |last1=Débarbat |first1=Suzanne |last2=Quinn |first2=Terry |title=Les origines du système métrique en France et la Convention du mètre de 1875, qui a ouvert la voie au Système international d'unités et à sa révision de 2018 |journal=Comptes Rendus Physique |date=January 2019 |volume=20 |issue=1–2 |pages=6–21 |doi=10.1016/j.crhy.2018.12.002 |doi-access=free |bibcode=2019CRPhy..20....6D}}</ref><ref>{{Cite web|last=Hirsch|first=Adolphe|date=1891|title=Don Carlos IBANEZ (1825-1891)|url=https://www.bipm.org/utils/common/pdf/obituaries/1891_CIPM_ES_IBANEZ-Don-Carlos.pdf|url-status=dead|archive-url=https://web.archive.org/web/20201026082704/https://www.bipm.org/utils/common/pdf/obituaries/1891_CIPM_ES_IBANEZ-Don-Carlos.pdf|archive-date=26 October 2020|access-date=|website=BIPM|pages=8–9}}</ref><ref>{{cite journal |last1=Drewes |first1=Hermann |last2=Kuglitsch |first2=Franz |last3=Adám |first3=József |last4=Rózsa |first4=Szabolcs |title=The Geodesist's Handbook 2016 |journal=Journal of Geodesy |date=October 2016 |volume=90 |issue=10 |pages=907–1205 |doi=10.1007/s00190-016-0948-z |bibcode=2016JGeod..90..907D |s2cid=125925505 |url=https://gfzpublic.gfz-potsdam.de/pubman/item/item_1981910_3/component/file_1985890/1981910.pdf}}</ref><ref>{{Cite web|last=Nacional|first=Instituto Geográfico|date=|title=Instituto Geográfico Nacional|url=https://www.ign.es/web/ign/portal/qsm-nuestra-historia|access-date=7 January 2021|website=Geoportal oficial del Instituto Geográfico Nacional de España|language=es-ES|archive-date=16 January 2021|archive-url=https://web.archive.org/web/20210116023805/https://www.ign.es/web/ign/portal/qsm-nuestra-historia|url-status=live}}</ref>
In November 1869 the French government issued invitations to join this commission. Spain accepted and [[Carlos Ibáñez e Ibáñez de Ibero]] took part in the Committee of preparatory research from the first meeting of the International Metre Commission in 1870. He became president of the permanent Committee of the International Metre Commission in 1872. In 1874 he was elected as president of the Permanent Commission of the [[International Association of Geodesy|European Arc Measurement]]. He also presided the General Conference of the [[International Association of Geodesy|European Arc Measurement]] held in Paris in 1875, when the association decided the creation of an international geodetic standard for the bases' measurement.<ref>{{Cite book|url=http://gallica.bnf.fr/ark:/12148/bpt6k949666|title=Histoire abrégée de l'astronomie / par Ernest Lebon,...|last=Lebon|first=Ernest (1846–1922) Auteur du texte|date=1899|publisher=Gauthier-Villars|location=Paris|pages=171|access-date=12 January 2018|archive-date=24 August 2017|archive-url=https://web.archive.org/web/20170824140556/http://gallica.bnf.fr/ark:/12148/bpt6k949666|url-status=live}}</ref> He represented Spain at the 1875 conference of the [[Metre Convention]], which was ratified the same year in Paris. The Spanish geodesist was elected as the first president of the [[International Committee for Weights and Measures]]. His activities resulted in the distribution of a platinum and iridium prototype of the [[metre]] to all States parties to the [[Metre Convention]] during the first meeting of the [[General Conference on Weights and Measures]] in 1889. These prototypes defined the metre right up until 1960.[[File:Bulletin de la Soci neuchloise des sciences naturelles (1898-) (20409300876).jpg|thumb|upright=0.75|Adolphe Hirsch, secretary of the [[International Association of Geodesy|International Geodetic Association]] and of the [[General Conference on Weights and Measures|International Committee for Weights and Measures]]]]