Question: Who was the French professor that the Robert brothers built the world's first hydrogen balloon for?

Jacques Alexandre César Charles (November 12, 1746 – April 7, 1823) was a French inventor, scientist, mathematician, and balloonist. <SEP> Alec Wilkinson (b. 1952 - ) is a writer who has been on the staff of "The New Yorker" since 1980.  According to "The Philadelphia Inquirer" he is among the "first rank of" contemporary American (20th and early 21st century) "literary journalists...(reminiscent) of Naipaul, Norman Mailer and Agee."  He is the author of ten books: "Midnights," (1982), "Moonshine," (1985), "Big Sugar," (1989), "The Riverkeeper," (1981), "A Violent Act, (1993), "My Mentor," (2002), "Mr. Apology," (2003), "The Happiest Man in the World," (2007), the latter about Poppa Neutrino, the only man to cross the Atlantic in a raft made of trash, and "The Protest Singer: An Intimate Portrait of Pete Seeger," (2009).  His most recent book is "The Ice Balloon," (2012), the account of the Swedish visionary aeronaut S.A. Andree's attempt, in 1897, to discover the North Pole by flying to it in a hydrogen balloon.  Before Wilkinson was a writer, he was a policeman in Wellfleet, Massachusetts, on Cape Cod, which is the subject of "Midnights," and before that he was a rock and roll musician, playing in a number of bands, including one in Berkeley, California with Tony Garnier, Bob Dylan's longtime bass player and bandleader.  Wilkinson began writing when he was twenty-four, showing work to William Maxwell, his father's friend, who in addition to being a novelist and short-story writer, had for forty years been an editor of fiction at The New Yorker.  They worked together closely for years.  Maxwell died in July 2000.  "My Mentor" describes their friendship.  Wilkinson's honors include a Lyndhurst Prize, a Robert F. Kennedy Book Award and a Guggenheim fellowship.  He is married, has a son, and lives in New York City.  He is also the brother of Leland Wilkinson. <SEP> Les Frères Robert were two French brothers.  Anne-Jean Robert (1758–1820) and Nicolas-Louis Robert (1760–1820) were the engineers who built the world's first hydrogen balloon for professor Jacques Charles; which flew from central Paris on August 27, 1783.  They went on to build the world's first manned hydrogen balloon, and on 1 December 1783 Nicolas-Louis accompanied Jacques Charles on a 2-hour, 5-minute flight.  Their barometer and thermometer made it the first balloon flight to provide meteorological measurements of the atmosphere above the Earth's surface. <SEP> Langworthy Historic District is a nationally recognized historic district located in Dubuque, Iowa, United States.  It was listed on the National Register of Historic Places in 2004.  At the time of its nomination it consisted of 110 resources, which included 94 contributing buildings, five contributing structures, nine non-contributing buildings, and two non-contributing structures.  This residential area was developed from the end of the American Civil War to the beginning of World War I.  Most of the houses were built between 1890 and 1910, with four large houses pre-dating the Civil War.  For the most part, the houses here are larger in scale and include examples of Victorian and the various revival and American Movement styles from the late 19th and 20th centuries.  The district is completely residential with no commercial or institutional buildings, and with only one multi-family house, a duplex.  Two houses were individually listed on the National Register: Langworthy House, an Octagon house from 1855, and the Garland House (1907).  The district derives its name from the Langworthy family who were early settlers in Dubuque and played a prominent role in the development of the local lead mining industry and the city itself.  Three of the brothers built houses here.