Jules Itier (his full names were Jules Eugene Alphonse) completed his schooling at Marseille in 1819 and then entered the administration of customs there. He later served as inspector of customs in Marseille, Lorient, Marennes, Oloron, Olette, and Belley. During the 1830s and 1840s he was actively involved with the scientific community. In 1842 he accompanied a commercial mission to west Africa (Senegal) and the Caribbean (Guyana and the Antilles) and two years later published Notes statistique sur la Guyana. Meanwhile he appears to have spent much of his free time studying geology, publishing papers on the lower Cretaceous rocks of Ain (a department in south-eastern France, 1841), the asphaltic rocks of the adjacent Jura (1841), the lower Cretaceous formations of Jura (1842), and the geology around Fort l'Ecluse (1842/3).
In 1843 he was appointed a member of a commercial mission to China, the East Indies and Oceania, and on his way there spent two weeks at the Cape. He paid particular attention to the geology of the south-western Cape and described it in a paper, "Notice sur la constitution geologique du Cap de Bonne-Esperance", which was published in the Comptes Rendus Hebdomadaires des Seances de l'Academie des Sciences (Vol. 19, pp. 960-970) in 1844. After his return to France he published a three volume book, Journal d'un voyage en Chine en 1843, 1844, 1845, 1846 (Paris, 1848-1853), in which he related his travels to China, Vietnam, Cambodia, Laos and the Philippines. His geological paper and a geological map of the area around Cape Town are included in Volume 1 (pp. 333-349). He also took a number of daguerreotypes of Chinese people and scenery in the Guangdong region - the earliest preserved photographs of China.
Itier did not add much to the earlier geological descriptions by Clarke Abel* and Captain Basil Hall*, of which he was probably unaware. He thought that the Cape Flats had been the site of a lake, into which the sandy limestones underlying much of the surface sand were laid down. The height of Table Mountain he ascribed to its haveing been uplifted by the underlying granite, without distrubing its horizontal layers, though he recognised that the same granite had strongly disturbed the local shales. Information about the interior of the country was supplied to him by Surveyor-General C.C. Michell*, and the surveyors W.F. Hertzog* and Mr Wentzel. The latter also gave him fossils from the Cedarberg, amongst which he recognized several species and dated the rocks from which they came to the Lower Silurian. His paper also included the first record of an anticline at the Cape, near Caledon. His geological map of the area around Cape Town is probably the earliest printed map of any part of southern Africa. It shows the granites north-west of Table Mountain, while the rocks of the Table Mountain Group are indicated as of Cambrian and Silurian age and shown to extend over a large area north of Tygerberg and in the Cape Peninsula. Limonite of quaternary age and modern deposits are shown on the Cape Flats, while a large patch of lacustrine limestone of quarternary age is shown south and south-east of Constantia.
Itier was an observant person and a lively writer. The first volume of his book also contains a chapter describing other aspects of his visit to the Cape: He climbed Table Mountain, unsuccessfully hunted a leopard at Hout Bay, and was not impressed with the local wine and viticulture, though the public library met with his approval.
Upon his return to France Itier took up administrative posts in Marseille (1846), Montpellier (1848), and Marseille again (1853). He wrote several publications on Chinese culture and commerce between 1847 and 1860, as well as notes on the edible plants of Java.