**Louis Raffy** was a French mathematician who published extensively on infinitesimal geometry.

- Casimir Raffy was a school teacher who wrote secondary school textbooks.
- At the Lycée Saint-Louis, Louis Raffy had brilliant successes in arts subjects as well as in science.
- Raffy was appointed as an assistant teacher at the Lycée Saint-Louis in 1875.
- In the following year he sat the examinations to enter the École normale supérieure and was awarded a place but he chose not to begin his university career at this time and he continued to work as a teacher at the Lycée Saint-Louis until 1879.
- Raffy published two papers which were based on his thesis, namely Détermination du genre d'une courbe algébrique Ⓣ(Determination of the genus of an algebraic curve) (1883) and the 85-page paper Recherches algébriques sur les intégrales abéliennes Ⓣ(Algebraic research on abelian integrals) (1883).
- On 19 October 1883 Raffy was appointed as a demonstrator in mathematics at the École Normale Supérieure and in the following year on 6 November 1884 he was put in charge of three courses at the Faculty of Sciences in Paris.
- Raffy published numerous papers, those published in 1884 and 1885 being the three papers Sur les transformations invariantes des différentielles elliptiques Ⓣ(On invariant transformations of elliptic differentials), Sur une proposition de M Hermite Ⓣ(On a proposition of Hermite) and Sur les quadratures algébriques et logarithmiques Ⓣ(On algebraic and logarithmic quadratures).
- In the list of publications which we have found written by Raffy, there are 77 papers and one book as we mentioned above.
- Raffy was appointed as a senior lecturer for the teaching of the agrégation, the highest teaching diploma in France, at the Faculty of Sciences from 7 November 1885.
- At the École Normale Supérieure, Raffy became a senior lecturer in analysis and, beginning in July 1897, he taught courses on the Elements of Analysis and on Mechanics.
- On 26 July 1904 he was appointed to the chair of Applications of Analysis to geometry at the Sorbonne, a chair was specially created for Raffy.
- Raffy is one of many people who make a huge contribution to mathematics yet their contributions have not been made in ways that lead to them being known to mathematicians today.
- Sadly Raffy's proof is incorrect but he was unlucky in that the error was as a result of using a result of Théodule Caronnet (born 1864) which was fallacious.
- There is another important contribution which Raffy made to mathematics in France which we must record and that is his contributions to the French Mathematical Society.
- Raffy died in 1910, at the age of 55.
- The President of the French Mathematical Society at the time of Raffy's death was Raoul Bricard (1870-1943).
- The memory of Louis Raffy, of all he did for our Society and dreamed of doing, will not fade from our memory.

Born 21 March 1855, Toulouse, Haute-Garonne, France. Died 9 June 1910, Paris, France.

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**O’Connor, John J; Robertson, Edmund F**: MacTutor History of Mathematics Archive