Joaquim Alves Gaspar
Biographic Data
| ID | 5016351 |
|---|---|
| NAME | Joaquim Alves Gaspar |
| GIVEN NAMES | Joaquim Alves |
| FAMILY NAME | Gaspar |
| SIGNATURE | GASPAR J A |
| AFFILIATIONS | University of Lisbon |
| ORCID | 0000-0001-8304-4583 |
| VERIFIED | Yes |
| TOTAL WORKS | 14 |
| TOTAL CITATIONS | 8 |
| AUTHOR COUNT | 14 |
| EDITOR COUNT | 0 |
| FIRST PUBLICATION YEAR | 2009 |
| LATEST PUBLICATION YEAR | 2026 |
| H-INDEX | 2 |
The Stand-Alone Charts of Battista Agnese
Magnetism, Navigation, and Cartography in the Early Modern Period
Following the introduction of the marine compass in Europe during the last decades of the thirteenth century, an intimate – and sometimes problematic – relationship between the Earth’s magnetism, navigation and nautical cartography developed. Because charts were constructed using uncorrected compass courses collected by pilots at sea, their coastlines often appeared distorted, reflecting the effect of magnetic declination. Although the phenomenon…
Kunstmann III
Among the few Portuguese charts surviving from the turn of the sixteenth century, the now lost Kunstmann III chart is the most enigmatic. Not only is it undated and unsigned but also its cartographical style differs greatly from the best-known contemporary Portuguese charts, namely those by Jorge de Aguiar and Pedro Reinel, as well as the Cantino planisphere. Although Kunstmann III has been studied by various twentieth-century authors, none has a…
Early Modern Nautical Charts and Maps
Of all the technical and scientific developments that made possible the European maritime expansion, the nautical chart is perhaps the least studied and understood. This fact is very surprising as it was with the information contained in those charts, and later imported to geographical maps and atlases, that the newly discovered lands were first shown to the European nations. There was, however, a deep incompatibility between these two cartograph…
Luís Teixeira, c.1585
KEYWORDS: Sixteenth centurymagnetic declinationisogonic linesgeomagnetic modellingnavigationnautical chartsplanisphereswind rosesLuís TeixeiraPetrus PlanciusFernando OliveiraJoão de LisboaPacific OceanPhilippine SeaNew Guinea
The Liber de existencia riveriarum ( c .1200) and the Birth of Nautical Cartography
The earliest known historical clue to what might be a primitive nautical chart is in a medieval manuscript of c.1200, the Liber de existencia riveriarum et forma maris nostri mediterranei, which describes the Mediterranean Sea. The body of the manuscript consists of an account of the Mediterranean and Black seas and the Atlantic coasts of Europe and northern Africa organized in 45 regional sections, each introduced by a short text setting out the…
What is a nautical chart, really? Uncovering the geometry of early modern nautical charts
The Planisphere of Juan de la Cosa (1500)
The chart drawn by Juan de la Cosa in 1500 contains an important innovation that distinguishes this planisphere from the other nautical charts produced at the time: the depiction of the equator and the Tropic of Cancer. This is a sign that astronomically observed latitudes may have been incorporated into the representation. In order to investigate such a possibility, the results of a cartometric analysis focused on the representation of the Atlan…
The Portuguese Atlas of Valladolid (Sixteenth Century)
A study of two Portuguese nautical charts of the sixteenth century, here designated as the ‘Atlas of Valladolid’, has been carried out with the aim of determining their origin and date of compilation. These charts are little known among the international community and have never been subjected to a cartometric analysis. Based on stylistic considerations, on the comparison of the toponyms with other contemporary charts and on the analysis of the l…
The Representation of the West Indies in Early Iberian Cartography
The earliest extant cartographic representation of the Americas is on the 1500 planisphere by the Cantabrian pilot Juan de la Cosa. On this nautical chart, the New World is represented according to the information collected by Spanish, English and Portuguese explorers in the last years of the fifteenth century. One of its most striking features is the large size of the Antilles, which are represented with a remarkably exaggerated scale relative t…
Globes, Rhumb Tables, and the Pre-History of the Mercator Projection
In this paper we show that, for historical reasons, the most likely way for Mercator to have drawn his map was by using a table of rhumbs. This is argued by examining in some detail the development of the concept of a rhumb line from its initial articulation by Pedro Nunes in 1537 to its advanced treatment in 1566. We also describe the intellectual debate that took place around this topic in Europe during that period. A hitherto neglected Portugu…
Squaring the Circle
In this study we assess the accuracy of the cartographic projection introduced by Mercator in his world map of 1569 aiming to identify its construction method. An error distribution of the latitude scale in the Organum directorium abacus was first determined in such a way as to be independent of the physical distortions that affected the sheets after printing. This distribution, which we have called the ‘error signature’ of the map, was then comp…
Blunders, Errors and Entanglements
The results of a cartometric analysis of the early sixteenth-century Portuguese chart of the world known as the Cantino planisphere are presented and discussed. The focus is on errors affecting the geographic lines and the representation of the coastlines. The outputs of three types of analyses are considered: a quantitative assessment of scales (scales of latitude and scales of distance); a qualitative evaluation of the implicit grid of meridian…
From the Portolan Chart of the Mediterranean to the Plane Chart of the Atlantic
Blunders, Errors and Entanglements
The results of a cartometric analysis of the early sixteenth-century Portuguese chart of the world known as the Cantino planisphere are presented and discussed. The focus is on errors affecting the geographic lines and the representation of the coastlines. The outputs of three types of analyses are considered: a quantitative assessment of scales (scales of latitude and scales of distance); a qualitative evaluation of the implicit grid of meridian…
Squaring the Circle
In this study we assess the accuracy of the cartographic projection introduced by Mercator in his world map of 1569 aiming to identify its construction method. An error distribution of the latitude scale in the Organum directorium abacus was first determined in such a way as to be independent of the physical distortions that affected the sheets after printing. This distribution, which we have called the ‘error signature’ of the map, was then comp…
The Liber de existencia riveriarum ( c .1200) and the Birth of Nautical Cartography
The earliest known historical clue to what might be a primitive nautical chart is in a medieval manuscript of c.1200, the Liber de existencia riveriarum et forma maris nostri mediterranei, which describes the Mediterranean Sea. The body of the manuscript consists of an account of the Mediterranean and Black seas and the Atlantic coasts of Europe and northern Africa organized in 45 regional sections, each introduced by a short text setting out the…
What is a nautical chart, really? Uncovering the geometry of early modern nautical charts
Globes, Rhumb Tables, and the Pre-History of the Mercator Projection
In this paper we show that, for historical reasons, the most likely way for Mercator to have drawn his map was by using a table of rhumbs. This is argued by examining in some detail the development of the concept of a rhumb line from its initial articulation by Pedro Nunes in 1537 to its advanced treatment in 1566. We also describe the intellectual debate that took place around this topic in Europe during that period. A hitherto neglected Portugu…
From the Portolan Chart of the Mediterranean to the Plane Chart of the Atlantic
Blunders, Errors and Entanglements
The results of a cartometric analysis of the early sixteenth-century Portuguese chart of the world known as the Cantino planisphere are presented and discussed. The focus is on errors affecting the geographic lines and the representation of the coastlines. The outputs of three types of analyses are considered: a quantitative assessment of scales (scales of latitude and scales of distance); a qualitative evaluation of the implicit grid of meridian…
Squaring the Circle
In this study we assess the accuracy of the cartographic projection introduced by Mercator in his world map of 1569 aiming to identify its construction method. An error distribution of the latitude scale in the Organum directorium abacus was first determined in such a way as to be independent of the physical distortions that affected the sheets after printing. This distribution, which we have called the ‘error signature’ of the map, was then comp…
Globes, Rhumb Tables, and the Pre-History of the Mercator Projection
In this paper we show that, for historical reasons, the most likely way for Mercator to have drawn his map was by using a table of rhumbs. This is argued by examining in some detail the development of the concept of a rhumb line from its initial articulation by Pedro Nunes in 1537 to its advanced treatment in 1566. We also describe the intellectual debate that took place around this topic in Europe during that period. A hitherto neglected Portugu…
The Portuguese Atlas of Valladolid (Sixteenth Century)
A study of two Portuguese nautical charts of the sixteenth century, here designated as the ‘Atlas of Valladolid’, has been carried out with the aim of determining their origin and date of compilation. These charts are little known among the international community and have never been subjected to a cartometric analysis. Based on stylistic considerations, on the comparison of the toponyms with other contemporary charts and on the analysis of the l…
The Representation of the West Indies in Early Iberian Cartography
The earliest extant cartographic representation of the Americas is on the 1500 planisphere by the Cantabrian pilot Juan de la Cosa. On this nautical chart, the New World is represented according to the information collected by Spanish, English and Portuguese explorers in the last years of the fifteenth century. One of its most striking features is the large size of the Antilles, which are represented with a remarkably exaggerated scale relative t…
What is a nautical chart, really? Uncovering the geometry of early modern nautical charts
The Planisphere of Juan de la Cosa (1500)
The chart drawn by Juan de la Cosa in 1500 contains an important innovation that distinguishes this planisphere from the other nautical charts produced at the time: the depiction of the equator and the Tropic of Cancer. This is a sign that astronomically observed latitudes may have been incorporated into the representation. In order to investigate such a possibility, the results of a cartometric analysis focused on the representation of the Atlan…
Luís Teixeira, c.1585
KEYWORDS: Sixteenth centurymagnetic declinationisogonic linesgeomagnetic modellingnavigationnautical chartsplanisphereswind rosesLuís TeixeiraPetrus PlanciusFernando OliveiraJoão de LisboaPacific OceanPhilippine SeaNew Guinea
The Liber de existencia riveriarum ( c .1200) and the Birth of Nautical Cartography
The earliest known historical clue to what might be a primitive nautical chart is in a medieval manuscript of c.1200, the Liber de existencia riveriarum et forma maris nostri mediterranei, which describes the Mediterranean Sea. The body of the manuscript consists of an account of the Mediterranean and Black seas and the Atlantic coasts of Europe and northern Africa organized in 45 regional sections, each introduced by a short text setting out the…
Early Modern Nautical Charts and Maps
Of all the technical and scientific developments that made possible the European maritime expansion, the nautical chart is perhaps the least studied and understood. This fact is very surprising as it was with the information contained in those charts, and later imported to geographical maps and atlases, that the newly discovered lands were first shown to the European nations. There was, however, a deep incompatibility between these two cartograph…
Kunstmann III
Among the few Portuguese charts surviving from the turn of the sixteenth century, the now lost Kunstmann III chart is the most enigmatic. Not only is it undated and unsigned but also its cartographical style differs greatly from the best-known contemporary Portuguese charts, namely those by Jorge de Aguiar and Pedro Reinel, as well as the Cantino planisphere. Although Kunstmann III has been studied by various twentieth-century authors, none has a…
Magnetism, Navigation, and Cartography in the Early Modern Period
Following the introduction of the marine compass in Europe during the last decades of the thirteenth century, an intimate – and sometimes problematic – relationship between the Earth’s magnetism, navigation and nautical cartography developed. Because charts were constructed using uncorrected compass courses collected by pilots at sea, their coastlines often appeared distorted, reflecting the effect of magnetic declination. Although the phenomenon…
The Stand-Alone Charts of Battista Agnese
Cartography (13 works) · Geography (13 works) · Historical Geography and Cartography (13 works) · Chart (10 works) · History (10 works) · History (9 works) · Mathematics (8 works) · Nautical chart (7 works) · Statistics (7 works) · Archaeology (5 works)