Ibáñez E Ibáñez De Ibero, Carlos

(b. Barcelona, Spain, 14 April 1825; d. Nice, France, 28 January 1891)

geodesy.

Ibáñez’ father, Martin Ibáñez de Prado, was a soldier and mathematician: a national hero for his participation in the sieges of Zaragoza and one of the first postulators of non-Euclidean geometry. In 1832, when Ibanez was barely seven, his father was assassinated for political reasons. The boy entered the Academy of Army Engineers in 1839, receiving training in both military and scientific subjects.

Ibáñez’ interest in geodesy was awakened by the practical courses he taught at the Academy of Engineers. In 1853 he joined the recently created commission for drawing up a national map. As a member he studied and planned a Geodimeter, known as the “Spanish rule,” to measure the best at Madridejos. In 1859 he devised a method for carrying out the census of rural and urban real property and for its conservation. He was cofounder (1866) and later president (until his death) of the International Geodesic Association. In 1875, as plenipotentiary envoy of the king, he attended the inauguration of the International Office of Weights and Measures, which he actively promoted in order to achieve a worldwide system of units of measure and decimal currency. He was also its first president.

At Ibáñez’ initiative the Census and Geographic Institute was created in 1870—he was its first director, as he was of the Corps of Geodesists (today know as the Geographical Engineers)—and in 1877 he was responsible for creation of the Statistics Corps. An early advocate of international scientific collaboration, he was a member of the Royal Academy of Sciences of Madrid, as well as the corresponding organizations of Barcelona, Paris, Berlin, Rome, Belgium, the United States, Buenos Aires, and Egypt.

Ibáñez’ was concerned mainly with precision in measurement and with scientific organization. He obtained a probable error of ±1/5,800,000 in geodesic bases, compared with the ±1/1,200,000 achieved until then. The fifteen-kilometer base measured in La Mancha was of particular note. At the request of the Swiss Confederation he carried out in 1880 the measurement of the central base of Aarberg at 2. 4kilometers.

As a result of Ibáñez’ initiative and eagerness to measure the globe, it was agreed in 1860 to remeasure the are of meridian from Dunkirk to Formentera. He projected the geodesic union of Europe with Africa, with an interruption of 270 kilometers, form Shetland to the Sahara; this had never been achieved by observations of a geodesic landmark. He carried out these observations in 1878 between the inhospitable peaks of Mulhacén and the Teticas in Spain and the Filhaoussen and the M’Sabiha in Algeria. The error in closing the triangles was on the order ± one second of arc, and the precision brought him the poncelet prize of the Academy of Sciences of Paris in 1889.Measurements of horizontal angles with±1/10,000 of degree in the centesimal system were achieved through his techniques.

BIBLIOGRAPHY

I. Original Works. The following are outstanding among Ibáñez’ twenty-eight publications: Manual del pontonero (Madrid, 1853); Aparato de medir bases (Madrid, 1859); Historia de los instruments de observacion en astronomia y geodesia (Madrid, 1863); NivelaciÓn geodésica (Madrid, 1864); Base central de la triangulación géodesica de Espan̄a (Madrid, 1869); Determinacion del metro y kilógramo internacionales (Madrid, 1875); Enlace geodésico y astronómico de Europa y Africa (Madrid, 1880); and Jonction geodesique et astronomique de l’Algerie avec l’ Espagne (Paris, 1886).

II. Secondary Literature. See the following, listed chronologically: A. Hirsch, Le Général Ibáñez’ C. I. de P. and M., necrological note (Neuchatel, 1891); Commemoration du centenaire de la naissance du General Ibáñez de Ibero (Paris, 1925); Inauguracion del monumento en memoria del Mulhacen (Madrid, 1957); and Carlos Ibáñez de Ibero, Biografia del General Ibanez de Ibero, Mulhacen (Madrid, 1957); and Episodios de la guerra de la independencia (Madrid, 1963).

J. M. LÓpez de Azcona