Welcome to my web site.
I am a historian of science working at the Centro Interuniversitário de História das Ciências e da Tecnologia, at the University of Lisbon (CIUHCT-UL), and I teach at the Master Program in the History and Philosophy of Science. I am presently Head of the Department for the History and Philosophy of Science.

Here you'll find information on my research, my papers, books and other topics. I have a number of ongoing projects with students and collaborators and will post some information here.

Research that's keeping me busy:

The edition of Pedro Nunes's Works (Obras de Pedro Nunes), by the Lisbon Academy of Sciences and the Calouste Gulbenkian Foundation is still my most absorbing project. The first six volumes are published: that is, ALL printed works by Pedro Nunes are now available in a modern, annotated edition. They can be bought at the Bookshop of the Calouste Gulbenkian Foundation. The volume on Nunes' manuscripts (vol. VII) is nearly completed; it should be ready in a couple of months. I am already working hard on vol. VIII (biographical materials and documents). See here for updated information.

In the past years I got more and more interested in problems in the history of cartography. I have been doing this work with Joaquim Gaspar. A few years ago we investigated the origins of the Mercator Projection -- and got some remarkable results; more recently we looked into the first charts with visual depictions of magnetic information, namely isogonic lines. Here are some of our papers: Joaquim Alves Gaspar and Henrique Leitão, "Squaring the Circle: How Mercator constructed his Projection in 1569", Imago Mundi, 66 (2014) 1-24; Henrique Leitão and Joaquim Alves Gaspar, "Globes, rhumb tables and the pre-history of the Mercator projection", Imago Mundi, 66 (2014) 180-195; Joaquim Alves Gaspar and Henrique Leitão, "How Mercator Did it in 1569: From Tables of Rhumbs to a Cartographic Projection", Newsletter of the European Mathematical Society, nº99 (March 2016) 44-49. More papers are submitted and will appear later this year. 

I am working with José Madruga Carvalho on the history of the Gregorian Reform of the Calendar in Portugal. The 1582 reform promoted by Pope Gregory XIII is a fascinating but sometimes very technical topic. There is an interesting body of documents on the correspondence between Portuguese astronomers and Roman authorities in the 16th century, but this was never studied in detail. A couple of years ago I traced unknown documents and we are now putting everything together and writing a book that we wish will become a reference work for the Portuguese reader.

I am working with Bernardo Mota on the edition of Francisco de Melo's mathematical works: Francisco de Melo: Obras Matemáticas. Melo (ca. 1490-1536) was a fine mathematician, perhaps the best Portuguese mathematician in the generation before Pedro Nunes. Volume I [Latin text and translation] was published last year and got the most prestigious prize in Portugal for academic translation. We are now working on volume II [Commentary and studies], which we plan to publish in late 2017. See here for more information.

Luana Giurgevich and I have been engaged for some years on a wide research about old libraries in Portugal. Our initial objective was to study the circulation of scientific books in Portugal but we soon realized that a broader approach was needed. We ended up examining in detail the contents of hundreds of old libraries; the result was our recent book: Clavis Bibliothecarum: Catálogos e Inventários de Livrarias de Instituições Religiosas em Portugal até 1834 - an exhaustive list of nearly 1.000 catalogues of ca. 400 ancient libraries plus hundreds of related documents. (This book was awarded a "Menção Honrosa" of the Prize "Lusitania - História", Academia Portuguesa da História, 2016). We are now researching the educational activities around these libraries and these ecclesiastical institutions.


March 2017. New site.

There is a new site, in English, on the Clavis Bibliothecarum and ancient libraries (most ecclesiastical) in Portugal. Still a bit experimental, but it will improve in the next weeks.

December 2016. New book:
Thomas Horst, Marília dos Santos Lopes, Henrique Leitão (eds).,
(Frankfurt am Main: Peter Lang, 2017). 245 pp. ISBN: 978-3-631-68113-8.

16 December 2016Biblioteca Pública de Évora .

Second conference of the series: Clavis Bibliothecarum: Novas Chaves de Interpretação. Biblioteca Pública de Évora. 

[For more information, see the Clavis bibliothecarum blog].

Recent and next speaking engagements:

15 May. "The Ajuda Archives and the History of Science". Biblioteca da Ajuda, Lisbon.

11 July. Plenary conference at the Encontro da Casa de Ciências, Lisboa.

Subpages (1): Old Stuff