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 Chair of the Department for the History and Philosophy of Science, at the Faculty of Sciences, University of Lisbon.

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. For more materials (but less explanation) go to my Academia.edu page.

Research that's keeping me busy:

Project RUTTER is now my most absorbing research commitment. This is a five-year Project funded by the European Research Council (ERC), to study early modern sailing directions (rutters) and ship's logbooks:  RUTTER: Making the Earth Global (ERC AdG 833438). Here is the RUTTER-SiteThe research team (Post-Docs, PhD students, staff) is superb. We have also a group of Advisors and some Associate Members. There is a blog, Reading Rutters, and a Twitter account. Within the framework of the Project, there is also the Lisbon Arabic Science and Philosophy Reading Group. In addition to research activities, we have a series of Seminars, a series of "Scholar meets RUTTER" events, Palaeography sessions, Arabic reading sessions, an internship program and many other activities. We are working on books and research papers, of course, but we also offer Technical Notes and Book Reviews to all interested. Be sure to follow our developments.

I am still continuing the edition of Pedro Nunes's Works (Obras de Pedro Nunes), by the Lisbon Academy of Sciences and the Calouste Gulbenkian Foundation. 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; Joaquim Alves Gaspar and Henrique Leitão,«What is a nautical chart, really? Uncovering the geometry of early modern nautical charts», Journal of Cultural Heritage, 29 (2018) 130-136Joaquim Alves Gaspar and Henrique Leitão, «Luis Teixeira, c.1585: The earliest known chart with Isogonic Lines», Imago Mundi, 70 (2018) 221-228; Joaquim Alves Gaspar and Henrique Leitão, «Early Modern Nautical Charts and Maps: Working through different cartographic paradigms», Journal of Early Modern History, 23 (2019) 1-28. 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. Here's an interview José Madruga and I gave about our forthcoming book, and here is a very short note we wrote: Henrique Leitão e José Madruga Carvalho, «1582: O Calendário Gregoriano: globalizar a marcação do tempo», in: Carlos Fiolhais, José Eduardo Franco, José Pedro Paiva (dir.), História Global de Portugal (Lisboa: Círculo de Leitores, 2020), pp. 409-414.

Ars nautica
 (1570), by Fernando Oliveira, is an extended compilation of information on nautical matters; it has been called an "encyclopaedia of sea and navigation" and this designation is not incorrect. Ars nautica is the last of the great Portuguese nautical texts of the sixteenth century still waiting for a modern edition. It was recently translated to Portuguese. I am presently reviewing this (excellent) translation looking at the technical aspects, and I will also prepare some notes.

Luana Giurgevich and I have been engaged for some years on a wide research of 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 900-page 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). Here's a review to the book, by Mário Santiago de Carvalho, in Revista Filosófica de Coimbra, 25 (2016) 462-464. The National Library [Biblioteca Nacional de Portugal] set up a Companion Site to the Book, with hundreds of digitised library catalogues. We are now researching the educational activities around these libraries and these ecclesiastical institutions.

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] is already published and got the prestigious prize for academic translation. Samuel Gessner published an extended Review of our book in Historia Mathematica, 45 (2018) 182-185. We are now working on volume II [Commentary and studies], which we plan to publish in 2019. See here for more information.


November 2020 - New Book
This is the cover of my new book (together with José María Moreno Madrid): Atravessando a Porta do Pacífico. Roteiros e Relatos da Travessia do Estreito de Magalhães, 1520-1620. It is a collection of rutters and other technical documents on the crossing of the Strait of Magellan during the first century of expeditions, 1520 to 1620.

The book will be available on Nov. 9.
(For my other books, see here).

October, 28, 2020

Newspaper Público asked me to write a small piece on Pedro Nunes's book of algebra: «"Quem sabe por algebra sabe scientificamente": O Libro de algebra (1567) de Pedro Nunes», Público, 28 Oct. 2020, p. 29.

October, 2020: The (famous) RUTTER Technical Notes:

TN 3: David Solomoni, Jesuits on Board: A Reasoned Bibliography on the Early Modern Jesuit Trans-Oceanic Sailing Experiences. (Here's a nice note about David's technical note at The Portal to Jesuit Studies, Boston College.)

September, 2020

RUTTER Project welcomes the new Interns (from Sept. 1st to Dec, 31): Miguel Cruz Fernandes, master student (History) at Universidade Nova and Tiago Rocha e Mello, master student (History) at Universidade de Lisboa.

August, 2020

I was interviewed by Helena Avelar and Luís Ribeiro, in their excellent ad Astra Podcast - Academic Conversations on the History of Astrology. Here is my interview: History of Science and Astrology(41'40''). The Podcast has sessions with Charles Burnett, Dorian Greenbaum, Martin Gansten, Günther Oestmann, Petra Schmidl, Jean-Patrice Boudet, among other scholars.

July, 22, 2020.

According to many, José Maria Pimentel's Podcast 45 Graus is the most interesting Portuguese podcast for cultural and academic matters. José Maria recently honoured me with an invitation for an interview. Here is the result: Os mitos surpreendentes da História da Ciência (1h44').

April-May, 2020Some news of the RUTTER Project during the Co-Vid 19 Pandemic:

RUTTER Book Reviews: Follow the most recent literature related to our topic.

Reading Rutters: This is the blog of the RUTTER Project.

The RUTTER Project is on Twitter: @ErcRutter. You can now follow our work in detail. 

March, 2020. Some of my recent papers:

Henrique Leitão, «The Making of a Hydraulics Expert: Estevão Dias Cabral (1734–1811)». In: Ana Duarte Rodrigues, Carmen Toribio Marín (eds), The History of Water Management in the Iberian Peninsula. Between the 16th and 19th centuries (Cham: Birkhäuser, 2020), pp. 369-384. Henrique Leitão e José Madruga Carvalho, «1582: O Calendário Gregoriano: globalizar a marcação do tempo», in: Carlos Fiolhais, José Eduardo Franco, José Pedro Paiva (dir.), História Global de Portugal (Lisboa: Círculo de Leitores, 2020), pp. 409-414. Henrique Leitão, «Inquisition and Science: Where do we stand now?», Annals of Science, 77 (2020) 127-133. Bernardo Mota e Henrique Leitão, «Francisco de Melo: entre Renascimento Matemático e Humanismo», in: Cristina Pimentel, Sebastião Tavares de Pinho, Maria Luísa Resende, Madalena Brito, Margarida Miranda (eds.), O Humanismo Português e Europeu. No 5º centenário do Cicero Lusitanus, Jerónimo Osório (1515-1580) (Coimbra: Imprensa da Universidade de Coimbra, 2020), pp. 57-67. 

March, 2020

Within the RUTTER Project, a Lisbon Arabic Science and Philosophy Reading Group has just started. It is coordinated by RUTTER researcher Juan Acevedo, with the collaboration of Inês Bénard da Costa.

January, 2020

Here's an interview José Madruga and I gave about our forthcoming book on Calendars in Portugal in the 16th century. Many thanks to Fernando Correia de Oliveira and his excellent blog Estação Chronographica.

January, 2020A sample of my papers in 2018-2019:

Henrique Leitão, «Instruments and artisanal practices in long distance oceanic voyages», Centaurus, 60 (2018) 189-202; Antonio Sánchez and Henrique Leitão, «Artisanal culture in early modern Iberian and Atlantic Worlds», Centaurus, 60 (2018) 135-140; Joaquim Alves Gaspar and Henrique Leitão, «Early Modern Nautical Charts and Maps: Working through different cartographic paradigms», Journal of Early Modern History, 23 (2019) 1-28. Luís Campos Ribeiro and Henrique Leitão, «Astrology with new eyes: The telescope in astrological prognostication», Journal for the History of Astronomy, 49 (2018) 345-362; Joaquim Alves Gaspar and Henrique Leitão, «Luis Teixeira, c.1585: The earliest known chart with Isogonic Lines», Imago Mundi, 70 (2018) 221-228; Joaquim Alves Gaspar and Henrique Leitão,«What is a nautical chart, really? Uncovering the geometry of early modern nautical charts», Journal of Cultural Heritage, 29 (2018) 130-136;

December, 2019

Just before the year ends, two excellent news: 
--- The Database of the Medea-Chart Project is now online. This is a superb research tool for anyone interested in medieval and early modern nautical cartography. (Medea-Chart is an ERC-funded Project led by Joaquim Gaspar: I am senior researcher at this Project. The Database was designed by Ricardo Vaz).
--- The Bibliographic Database of CIUHCT, Bibliografia de História da Ciência, Tecnologia e Medicina, is now online. It contains bibliographic references of all publications about Portugal, or authored by Portuguese scholars, on History of Science, Technology and Medicine, in the period 2000 to 2015. (The Database is a collective output of CIUCHT, but mostly done by João Machado.)

November, 2019

Newspaper Expresso invited me to write a brief Preface to their republication of Stefan Zweig's Magellan. They wanted specifically an historian of science to write such a text.

October 2019

The Bibliotheksmagazin of the Staatsbibliothek Berlin published an article  about the Lisbon/Berlin collaboration to study Thurneyser's manuscript: Bernard Herold, Thomas Horst, Henrique Leitão, Gabriele Kaiser, «Zu Lissabon Angefangen Anno Christi 1555. Die Handschrift Ms. Germ. Fol. 97 ist online zugänglich», Bibliotheksmagazin 3/19 (2019) 60-65. See here for the whole issue of the magazine. 

1 September, 2019

Project RUTTER officially started today. RUTTER: Making the Earth Global (ERC AdG 833438) is a new, ambitious, five-year Project to study early modern sailing directions (rutters) and ship's logbooks. I plan to make public some results along the way. This is the Web page of the RUTTER Project. And here is a notice and interview I gave to my Faculty's news service.

May, 2019. New book:

Bernardo Jerosch Herold, Thomas Horst, Henrique Leitão (eds.),
A História Natural de Portugal de Leonard Thurneysser zum Thurn, ca. 1555-1556
(Lisboa: Academia das Ciências de Lisboa, 2019)
ISBN: 978-972-623-368-8, 129 pp. [free download here]

September, 2018. Frontiers in the History of Science.

 New series: Frontiers in the History of Science, Birkhäuser, Basel. Editor: Vincenzo de Risi. I am one of the Associate editors.
Frontiers in the History of Science is designed for publications of up-to-date research results encompassing all areas of history of science, primarily with a focus on the history of mathematics, physics, and their applications. Graduates and post-graduates as well as scientists will benefit from the selected and thoroughly peer-reviewed publications at the research frontiers of history of sciences and at interdisciplinary “frontiers”: history of science crossing into neighboring fields such as history of epistemology, history of art, or history of culture. 

July 2018 - Melo's Obras Matemáticas is online (and free)!

It recently came to my attention that my book with Bernardo Mota: Francisco de Melo: Obras Matemáticas[vol. I: Texto Latino e Tradução] (Lisboa: Centro de Estudos Clássicos e Biblioteca Nacional de Portugal, 2014) is now fully downloadable (!) at the Repositório da Universidade de Lisboa.

See also the recent detailed Review of the book by Samuel Gessner here: Historia Mathematica, 45 (2018) 182-185

Subpages (1): Old Stuff