Marino Ghetaldi was educated in Ragusa, then he moved to Rome before travelling extensively in Europe. In Rome he was influenced by Clavius. He then studied at Antwerp and at Paris where he was greatly influenced by Viète. He then spent two years in England.
Ghetaldi was offered the chair of mathematics at University of Louvain but he turned the offer down.
Ghetaldi's first paper appeared in 1603 and it was on Archimedes. In this he gave an accurate table of specific weights of solids and liquids. In a second work he studied parabolas obtained as sections of a right circular cone.
Viète had been working on constructing Apollonius's lost works. In fact Viète was often known as Apollonius Gallus because of this. Ghetaldi took over this work of Viète. He followed Pappus's description of the contents of certain lost books and to do this he had to solve the problems which the books were supposed to contain.
In 1607 Ghetaldi produced a pamphlet with 42 problems with solutions Variorum problematum colletio. These contain early application of algebra to geometry.
Ghetaldi's work is described in Herigone's 1634 work Cursus mathematicus.
It is interesting to look at the kind of person Ghetaldi was. He turned down a chair at Louvain when he was a young man. Descriptions of him say he had the morals of an angel and to be a Ragusan gentleman of discernment.
Article by: J J O'Connor and E F Robertson
December 1996