Bombelli, Rafael,1526–1572, Italian mathematician and engineer, b. Bologna. When a marsh reclamation project (c.1550–1560) in the Tuscan Appenines on which he was an engineer was suspended, he penned a treatise on algebra, in which he dealt with the theory of imaginary numbers and negative numbers. For this work, he is regarded as the discoverer of complex numbers. He subsequently was involved in Rome in unsuccessful projects to repair the Ponte Santa Maria bridge and drain the Pontine Marshes. After working on a translation of a manuscript of the Greek mathematician DiophantusDiophantus
, fl. A.D. 250, Greek algebraist. He pioneered in solving a type of indeterminate algebraic equation where one seeks integer values for the unknowns; work in this field is known as Diophantine analysis. Only 6 of the 13 books with which he is credited are extant.
..... Click the link for more information. , Bombelli undertook a revision of his Algebra, three volumes of which were published in 1572. The incomplete manuscript of the last two volumes were discovered in 1923 and published in 1929.