Vocation : Engineer : Mechanical

Nicolas Léonard Sadi Carnot (French pronunciation: [nikɔla leɔnaʁ sadi kaʁno]; 1 June 1796 – 24 August 1832) was a French mechanical engineer in the French Army, military scientist and physicist, often described as the "father of thermodynamics". He published only one book, the Reflections on the Motive Power of Fire (Paris, 1824), in which he expressed the first successful theory of the maximum efficiency of heat engines and laid the foundations of the new discipline: thermodynamics. Carnot's work attracted little attention during his lifetime, but it was later used by Rudolf Clausius and Lord Kelvin to formalize the second law of thermodynamics and define the concept of entropy. Driven by purely technical concerns, such as improving the performance of the steam engine, Sadi Carnot's theoretical work laid important foundations for modern science as well as technologies such as the automobile and jet engine.
His father Lazare Carnot was an eminent mathematician, military engineer, and leader of the French Revolutionary Army.

Walter Gempp (13 September 1878 – 2 May 1939) was a German engineer. From 1922 to 1933 he was the sixth head of the Berlin Fire Brigade.
After studying mechanical engineering, Gempp joined the Berlin Fire Department in 1908. He was given the project of developing a motorized fire extinguishing service, and in 1908 he produced the first engine-powered hose truck. In 1923 he became chief fire commissioner in Berlin.Gempp was head of the Berlin fire department at the time of the Reichstag fire on 27 February 1933, personally directing the operations at the incident. On 25 March he was dismissed for presenting evidence that suggested Nazi involvement in the fire. Gempp asserted that there had been a delay in notifying the fire brigade and that he had been forbidden from making full use of the resources at his disposal.
In 1937, he was arrested for abuse of office. Despite his appeal, he was imprisoned. On 2 May 1939, Gempp was found dead in his cell. Some literature suggests that he was murdered by the National Socialists. Other authors state that Gempp took his own life in order to secure his family's pension entitlements, which would have been lost if the judgment against him had become final.

Antoine-Joseph Yvon Villarceau (15 January 1813 – 23 December 1883) was a French astronomer, mathematician, and engineer.
He constructed an equatorial meridian-instrument and an isochronometric regulator for the Paris Observatory.
He wrote Mécanique Céleste. Expose des Méthodes de Wronski et Composantes des Forces Perturbatrices suivant les Axes Mobiles (Paris: Gauthier-Villars, 1881) and Sur l'établissement des arches de pont, envisagé au point de vue de la plus grande stabilité (Paris: Imprimerie Impériale, 1853).
He is the eponym of Villarceau circles, which are two circular sections of a torus other than the two trivial ones.
A short street in the 16th arrondissement of Paris is named after Villarceau.

Karl Freiherr von Drais (full name: Karl Friedrich Christian Ludwig Freiherr Drais von Sauerbronn; 29 April 1785 – 10 December 1851) was a noble German forest official and significant inventor in the Biedermeier period. He was born and died in Karlsruhe. He is seen as "the father of the bicycle".

Louis Zimmer (8 September 1888 – 12 December 1970) was an astronomer and clockmaker to the King of Belgium. Most notably in 1930 he built the Jubilee (or Centenary) Clock, which is displayed on the front of the Zimmer tower. The Zimmer tower (Dutch: Zimmertoren) is a tower in Lier, Belgium, also known as the Cornelius tower, that was originally a keep of Lier's fourteenth-century city fortifications. In the museum near the tower in addition to many of Zimmer's other clock is the huge clock he constructed for the 1935 Brussels International Exposition. This is the clock was sent to the United States for the 1939 New York World's Fair. In June 1970 he was proclaimed Honorary Citizen of Lier. The asteroid Zimmer (№ 3064)(1984 BB1), was named after him in 1984.

Louis-Émile Bertin (23 March 1840 – 22 October 1924) was a French naval engineer, one of the foremost of his time, and a proponent of the "Jeune École" philosophy of using light, but powerfully armed warships instead of large battleships.