Vocation : Science : Geology

Joseph Thomson (14 February 1858 – 2 August 1895) was a British geologist and explorer who played an important part in the Scramble for Africa. Thomson's gazelle and Thomson's Falls, Nyahururu, are named after him. Excelling as an explorer rather than an exact scientist, he avoided confrontations among his porters or with indigenous peoples, neither killing any native nor losing any of his men to violence. His motto is often quoted to be "He who goes gently, goes safely; he who goes safely, goes far."

Beno Gutenberg (; June 4, 1889 – January 25, 1960) was a German-American seismologist who made several important contributions to the science. He was a colleague and mentor of Charles Francis Richter at the California Institute of Technology and Richter's collaborator in developing the Richter magnitude scale for measuring an earthquake's magnitude.

Alphonse Francois Renard (27 September 1842 – 9 July 1903), Belgian geologist and petrographer, was born at Ronse, in East Flanders, on 27 September 1842. He was educated for the church of Rome, and from 1866 to 1869 he was superintendent at the college de la Paix, Namur.In 1870 he entered the Jesuit Training College at the old abbey of Maria Laach in the Eifel, and there, while engaged in studying philosophy and science, he became interested in the geology of the district, and especially in the volcanic rocks. Thenceforth he worked at chemistry and mineralogy, and qualified himself for those petrographical researches for which he was distinguished.In 1874 he became professor of chemistry and geology in the college of the Belgian Jesuits at Leuven, a few years later he was appointed one of the curators of the Royal Natural History Museum at Brussels, and in 1882 he relinquished his post at Louvain. In 1888 he was chosen professor of geology at the University of Ghent, and retained the post until the close of his life. Meanwhile, he had been ordained priest in 1877, and had intended to enter the Society of Jesus. He was known as the Abbé Renard; but, as remarked by Sir A. Geikie, as years passed, the longing for mental freedom grew ever stronger, until at last it overmastered all the traditions and associations of a lifetime, and he finally separated himself from the church of Rome.His first work, written in conjunction with Charles-Louis-Joseph-Xavier de la Vallée-Poussin (1827–1904), was the Mémoire sur les caractères minéralogiques et stratigraphiques des roches dues plutoniennes de la Belgique et de l'Ardenne française (1876). In later essays and papers he dealt with the structure and mineral composition of many igneous and sedimentary rocks, and with the phenomena of metamorphism in Belgium and other countries. In acknowledgment of his work, the Bigsby Medal was awarded to him in 1885 by the Geological Society of London. Still more important were his later researches connected with the Challenger Expedition. The various rock specimens and oceanic deposits were submitted to him for examination in association with Sir John Murray, and their detailed observations were embodied in the Report on the Scientific Results of the Voyage of H.M.S. Challenger Deep Sea Deposits (1891). The more striking additions to our knowledge included the detection and description of cosmic dust, which as fine rain slowly accumulates on the ocean floor; the development of zeolitic crystals on the sea-bottom at temperatures of 32 °F (0 °C) and under; and the distribution and mode of occurrence of manganese nodules and of phosphatic and glauconite deposits on the bed of the ocean. Renard died at Brussels on 9 July 1903.Rue Alphonse Renard, in western Ixelles, is named in his honor. In addition, the mineral renardite was named in his honor in 1928.

Pedro José Amadeo Pissis Marín (Brioude, France, May 17, 1812 – January 21, 1889, Santiago de Chile) was a French geologist who served the Chilean government in the 19th century. He played an influential role in the cartography of Chile. Pissis worked in Brazil and Bolivia before he arrived to Chile. He left Bolivia due to political problems and was preparing his departure to France in Valparaíso when Chilean minister Manuel Camilo Vial contacted him to do a geologic and mineralogic description of the Republic of Chile. Monte Pissis, the third highest mountain in the Western Hemisphere and second highest volcano in the world is named after him.

Charles-Victor Mauguin (French: [ʃaʁl.vik.tɔʁ mo.gɛ̃]; 19 September 1878 – 25 April 1958), more often Charles Mauguin, was a French mineralogist and crystallographer. He and Carl Hermann invented an international standard notation for crystallographic groups called Hermann–Mauguin notation (also sometimes called international notation).

Ernest-François Mallard (4 February 1833 – 6 July 1894) was a French mineralogist and a member of the French Academy of Sciences. He is also notable for his work with Henri Louis Le Chatelier in combustion as applied to mining safety.

Edmond Hébert (12 June 1812 – 4 April 1890), French geologist, was born at Villefargau, Yonne.
He was educated at the College de Meaux, Auxerre, and at the École Normale in Paris. In 1836 he became professor at Meaux, in 1838 demonstrator in chemistry and physics at the École Normale, and in 1841 sub-director of studies at that school and lecturer on geology. In 1857 the degree of D. es Sc. was conferred upon him, and he was appointed professor of geology at the Sorbonne.There he was eminently successful as a teacher, and worked with great zeal in the field, adding much to the knowledge of the Jurassic and older strata. He devoted, however, special attention to the subdivisions of the Cretaceous and Tertiary formations in France, and to their correlation with the strata in England and in southern Europe.To him we owe the first definite arrangement of the Chalk into palaeontological zones (see "Table" in Geol. Hag., 1869, p. 200). During his later years he was regarded as the leading geologist in France.He was elected a member of the Académie des sciences in 1877, Commander of the Legion of Honour in 1885, and he was three times president of the Geological Society of France. He died in Paris on 4 April 1890.

Gustave Émile Haug (19 June 1861 - 28 August 1927) was a French geologist and paleontologist known for his contribution to the geosyncline theory.

Léon Alexandre Guillet (11 July 1873 – 9 May 1946) was a French metallurgist who studied the properties of metal alloys and developed martensitic and austenitic stainless steels. He served as a professor of metallurgy at the École Centrale Paris where he was a director from 1923 and played a key role in putting materials research on a scientific footing.
Guillet was born in Saint Nazaire (Loire Atlantique) and in 1894 he went to the school of art and manufacture where he met Henri Le Chatelier who guided him. His doctoral thesis was on aluminium alloys and the work was done at Dion-Bouton and at Le Chatelier's laboratory in the Ecole des Mines. He then became a consultant at Dion-Bouton and worked with several companies. In 1906 he went to teach metallurgy and became a full professor in 1908 and worked there until 1942 while also consulting in the industry. In 1923 he became director of the school of arts and manufacture where he brought major changes including a foundation in scientific theories in engineering. During World War I he was involved in the design and manufacture of artillery shells. During World War II, in 1939, he was again put in charge of naval artillery at the Ruelle Foundry in Angoulême as honorary artillery lieutenant-colonel. Guillet published his major metallurgical works including Traité de métallurgie génerale (1922), Les méthodes d'étude des alliages métalliques (1923), and Trempe, recuit, revenue (2 volumes, 1928–1931). He examined steels made with nickel, manganese, chromium, tungsten, as well as copper and aluminium alloys. He examined the heat treatment of alloys.Guillet was elected to the Academy of Sciences in 1925, proposed by Le Chatelier. Guillet married Marie Béatrice Edwidge Soulier in 1898 and they had a daughter and a son, Léon Pierre Adolphe Guillet (1908–1991), who also became a metallurgist.