In 1839 he began to study engineer in the army academy. In 1853, he published: Manual del pontonero and, in the same year, he became a member of the committee that had to made a map of Spain, this was how he began to be interested in geodesic science.

Joan Isern was born in Can Batlló de Setcases on September 25, 1821. During the 1849-50 academic year, in which he was taking the second year of Medicine, although he was already recognized for his knowledge of phytology, instructions were sent from Madrid to all the Spanish universities to propose candidates to occupy the position of botanical collector of the Museum of Natural Sciences. The University of Barcelona proposed the name of Joan Isern who went to Madrid, where he worked for more than a decade as collector and curator of the Museum and Royal Botanical Garden.