Voyages, Discoveries and the Renaissance | Medieval Period | Geography

In this article we will discuss about the impact of voyages, discoveries and the renaissance on geography.

It is surprising to note that the exploring activities among the Arabs and the Chinese gradually came to an end. There was no great Arab traveller after lbn-Batuta in the fourteenth century, and in China, the end came after the seventh expedition of Cheng Ho in 1433.

But the exploring activities in Europe all of a sudden increased in the fifteenth century and this time they were well-planned and supported by governments or by merchant companies and expedition to the open oceans were preferred. It was a major turning point in the world geographical scholarship as new discoveries largely removed the doubts created by the earlier notions and concepts.

These exploring activities were motivated by religious and economic factors – the zeal to spread the Christian faith and the need to replenish the European supplies of precious metals and spices, and the desire for personal wealth.

The desire to liberate the greater part of Spain and Portugal from the Arab rule, as a part of a unified national consciousness, accelerated the zeal to spread the Christian faith. Increasing trading activities with a view to provide financial support for trade necessitated the need for a supply of gold and silver or valuable gems.

Prince Henry of Portugal is credited with organising voyages and expeditions to the open seas. The fall of Arab stronghold on the southern side of the strait of Gibraltar under his command in 1415, widened the horizon of the Portuguese world. Prince Henry is also credited with the establishment of the world’s first geographic research institute in 1418.

At Sagres, he built a palace, a chapel, an astronomical observatory, and buildings to store collections of maps and manuscripts, and houses for the institute staff. He may be compared with Roger II of Sicily who found Palermo for the academic activities. Like Roger II, Prince Henry brought scholars of all faiths to Sagres from all around the Mediterranean. Master Jacome of Majorca was the chief geographer.

The purpose behind the setting up of Sagres was to improve and teach the methods of navigation to Portuguese sea captains, to teach the new decimal mathematics, and to shift the evidence from documents and maps concerning the possibility of sailing southward along the African coast and thence to the Spice Islands.

Prince Henry’s captains successfully sailed to the three groups of islands of the Atlantic off North Africa and Europe that included the Canary Islands (Ptolemy’s Fortunate Islands), the Madetra Islands, and the Azores. The discovery of these islands by the Portuguese sailors brought about changes in the perception about the high seas, and the bearings which were wrongly shown on the Portolano Chart of 1351 were made accurate.

In 1434, one of the trusted captains of Prince Henry, Gil Eannes sailed south of the latitude of Bojador and turned eastward. He made his first attempt to sail to Cape Bojador in 1433, but was forced to return to Sagres. The contemporary belief was that the strong current of water along the coast formed eddies with much foam off the end of the cape and the water was boiling, and the people would become black if they moved beyond the cape.

It is reported that when Gil Eannes reached the shore, the water was not boiling and no one turned black. The ‘cape Bojador puzzle’ thus came to an end. The very next year, Portuguese ships sailed 350 miles south of Bojador.

Under Prince Henry’s constant patronage, the Portuguese sailors had sailed far enough south to reach the southern zone of transition between the desert and the humid country beyond. In 1473, a Portuguese ship crossed the equator without burning. This expedition successfully encountered what the Greek geographers had said earlier.

Between 1486 and 87, Bartholomew Dias sailed southward from the equator and to avoid stormy weather, he sailed far out westward away from the land and reached the coast of southern Africa at Algoa Bay (Port Elizabeth). While coming back, he passed Cape Agulhas, the southernmost point of Africa, and then the Cape of Good Hope.

Between 1497 and 1499, Vasco da Gama made his famous voyage across the Arabian Sea to reach Calicut on the west coast of India. He made a wide circle out into the Atlantic before turning eastward along the latitude of Cape Agulhas and voyaged along the coast of Mozambique and then sailed eastward. By the time Vasco da Gama returned to Lisbon, he had sailed 24,000 miles in more than two years. In 1510, the Portuguese took Goa on the west coast of India.

In 1511, they set up a base at Malacca on the strait between Malay Peninsula and Sumatra. Japan was approached in 1542. In 1557, the Portuguese leased Macao from the Chinese and in 1590 they reached Taiwan and gave it the Portuguese name, Formosa.

Undoubtedly, the geographical explorations, conducted by the Portuguese in the fifteenth and sixteenth centuries, seemed to have collected a variety of information about the places, never visited by any European, and removed the doubts about certain areas in the Atlantic Ocean, created by the wrong notions of the earlier Greek geographers.

The voyages of Christopher Columbus during 1492-1504, across the North Atlantic Ocean also marked a turning point in the world’s history of expeditions. He was to have discovered Asia as he thought earlier about the possibility of sailing westward to Asia.

He read Ptolemy’s ‘Geography’, Cardinal Pierre d’ Ailly’s ‘Imago mundi’ and the books of Aeneas Silvius (Pope Pius II). He was familiar with the accounts of Marco Polo. But ever since he started his voyage, he carried forward with him certain wrong notions about the circumference of the Earth, and the eastward extension of the known lands of the Earth.

Columbus spent a few years in Portugal to study what was left of the institute at Sagres founded by Prince Henry in 1418. He reckoned that the east coast of Asia was located just about where the east coast of Mexico is actually located. However, his belief was strengthened when he found the southern coast of Cuba and the coast of Central America trending towards south-west, just as the coast of Asia was shown on Ptolemy’s map.

When he heard from the Indians of Central America that there were sources of gold only a short distance west and that there was another great ocean beyond, he was sure it must be the Indian Ocean. He also thought that there must be a strait connecting the Caribbean with the Indian Ocean as he witnessed the great flow of water along the northern coast of South America.

He was the first explorer to discover and make use of the wind system of the Atlantic. Columbus had known about the presence of easterly winds in the low latitudes and of westerlies in the higher latitudes.

Columbus is credited with the Treaty of Tordessilles which was agreed upon by Spain and Portugal in 1494. Under the treaty, the world was divided between these two countries, and the dividing line was to be drawn 270 leagues west of the Azores or 370 leagues west of the Cape Verde islands. Portugal got exclusive rights over the land east of that line, Spain to the west of it.

The treaty gave Portugal a free hand in the Indian Ocean and Columbus got a free hand in the lands he discovered west of the Atlantic. The treaty of Tordessilles marked the beginning of the concept of the geometric boundary which in the nineteenth century became accepted principle for the European powers for the division of their colonial territories in Africa and elsewhere.

Magellan, or Fernao de Magalhaes, was the first European explorer to have reached eastern Asia by sailing west. His expedition began in 1518 and he sailed along the Brazilian coast, and in 1520 he found the entrance to the strait that bears Magellan’s name. It took him 30 days to pass through the 360 miles strait.

He moved in a north-westerly course for 98 days before he reached the Island of Guam. He reached the Philippines in 1521. Magellan, on a previous voyage for Portugal, had reached the Spice Islands (the Moluccas) which are east of the Philippines. Therefore, at this point he had become the first man to sail all the way around the Earth.

Certain inventions in the sixteenth, seventeenth and eighteenth centuries further enhanced the contemporary knowledge about the Earth, as some of the major problems faced by the explorers had to be solved. To achieve perfection and accuracy, navigation was the major problem that the sailors had to be confronted with.

The preparation of the iso-thermic map by Edmund Halley who in 1699-1700 noted the magnetic variation he plotted on the map during a voyage, suggested that it was not the same for each longitude. In the sixteenth century, the cross-staff was invented.

The measurement of the Sun’s altitude by its shadow was made possible by the invention of the back- staff by John Davies. John Hadley invented the octant in 1731. The sextant, still in use, was a yet later improvement based on the principle first adopted by Davies. The British sailors are credited with the invention of the log which solved the problem concerning the measurement of speed at the sea.

This is invention solved the problem of measuring distance and direction and fixing the position on the surface of the Earth, and the determination of latitude, as it involved observations of the height of certain stars of the Sun above the horizon. These inventions, in fact, revolutionised the navigation as a result of which newer and correct ideas flourished with regard to the high seas and oceans.

In spite of some achievements in tackling the problem of perfecting the accuracy of navigation, there was more to be done because, until the longitude could be precisely determined, navigation remained dangerously inaccurate. The measurement of longitude needed some way of keeping accurate time at sea.

It was felt as early as 1522 that a dependable time piece would solve the longitude problem. It was in 1657 that Christian Huygens invented the pendulum clock, but it was no good at sea. The need for an accurate clock was felt in 1707 when an English fleet was wrecked on the Scilly Island because the navigator had a wrong estimation of longitude.

In 1714, the British Parliament offered a reward to any person or persons who could devise a pendulum clock to measure time at sea with sufficient accuracy. John Harrison is credited with the invention of a pendulum clock which proved to be so accurate that for the first time in humankind s long effort to gain useful knowledge about the Earth, an explorer could tell about its exact position.

Harrison was given the reward in 1775. By this time French and Swiss clock-makers were almost ready with their models. After this date, navigators could measure longitude with the same precision with which they could measure latitude.

One of the major consequences of the age of discoveries and invention was that of an organised cartographic revolution which occurred simultaneously both at Venica and Genoa. The need was felt to correct the works of the ancient cartographers. It was as early as 1.459 that Fra Mauro for the first time prepared a map showing the Indian Ocean open to the south, thereby breaking the Ptolemaic tradition of enclosing that ocean.

It is not known how he could come to know about an open Indian Ocean, but his map like the other maps of his time was oriented towards the south. Martin Behaim of Nuremberg was the first cartographer to have devised the world’s first globe in 1490.

He was helped by a painter named Jorge Glockendon in the preparation of the globe which was based on the small estimate of the Earth’s circumference, but it was strange enough that Columbus could never have known of Behaim’s globe.

In 1500, Juan de la Cosa prepared a map using the observations obtained from the first three voyages of Christopher Columbus and also from John Cabot’s voyage to North America. Martin Woldseemuller in 1507 produced the first world map showing America as a separate continent and not the eastern continuation of Asia.

The word America was used by him to denote the new continent. This was largely because he thought that Amerigo Vespucci had reached the new continent before Columbus or because Amerigo was definitely the first explorer to identify the newly discovered land as a separate continent.

However, for navigation, this map was not found to be more useful than other maps of this period that made use of the Portolano principle of design. Explorers had already found that when they followed any of the straight lines on these maps for long voyages, they did not arrive at expected destination. The contemporary need was for a new kind of projection which could make it possible to show the curved surface of the Earth on a flat paper or parchment.

In 1530, Peter Apian prepared a heart-shaped map of the Earth with the curved lines of latitude and longitude. But Apian’s projection was found to be defective because distance and direction on the projection appeared to be distorted.

Gerard Krema, or Gerardus Mercator, produced a graticule for the world by joining two heart-shaped projections, one for each hemisphere. Mercator is credited for his projection which he produced in 1569 for the world. This projection was the only contemporary projection/map being used for navigation in the low and middle latitudes.

Though the projection offered solution to the problems of navigation and enabled the navigators/sailors to reach the desired destination by sailing the great circle (shortest) route, it was not widely adopted probably because of it being too mathematical. The sailors who were not trained in mathematics found difficulties in believing that a short line was not the shortest distance between two points on the surface of a sphere.

It was not until 1599 when Edward Wright produced the trigonometric tables that made it possible for other people to produce Marcator’s projection. It is also believed that in 1511, Erhard Etzlaub of Nuremberg prepared a map of Europe and Africa on the same principle as that of Mercator. It is not known whether Mercator knew about this or not.

Abraham Ortelius of Antwerp produced the Ortelius atlas—’Theatrum orbis terrarum’ in 1570. Amsterdam gradually grew up as the major centre for the publication of atlases and wall maps, especially in the seventeenth century, breaking the tradition of Venice and Genoa in the art of map making.

Nicholas Sausond’ Abbeville was the first producer of world atlases in France, and founded a ‘dynasty of cartographers’ in the seventeenth century which produced maps and atlases for over a century. During the seventeenth and eighteenth centuries the map-makers only slowly revised their maps to include the newest information and to acknowledge the existence of gaps in their information.

The period between 1768 and 1779 was a landmark in the history of geographical thought. Erroneous idea which the Christian Europe inherited from Ptolemy during the Middle Ages after his geography was translated into Latin, stipulated the presence of a great southland which he called terra australis incognita which enclosed the Indian Ocean on the south.

Though the Arab traders had known that the Indian Ocean was open to the south and the map of Fra Mauro showed it, there were many who either did not know about the Arabic writings or disputed the travel accounts of the Arab scholars.

It was during his first voyage (1768-71) that Captain Cook found no land at about 40°S latitude. His second voyage (1772-74) finally removed the wrong notion about Ptolemy’s great southland, as he sailed as far as 71°10′ south latitude.

However, through Captain Cook it became known that there was an ice-covered land farther south, which he had been unable to reach. In 1778, Captain Cook again sailed into the Arctic Ocean through the Berring Strait, but was unable to move further because of ice-floes at 70°44′ N.

Voyages, inventions and cartographic precision and innovations seemed to have solved certain major problems regarding navigation, determination of longitude, projection, and those arising out of many erroneons concepts of Ptolemy.

But in spite of all these major achievements in an era of discoveries, the problem concerning the shape of the Earth remained to be solved. The problem was whether to accept what Isaac Newton and Christian Huygens said in 1687 that the Earth must be flattened at the poles and it must bulge at the equator.

In 1720, Jacques Cassini contrasted what Newton and Huygens said about the shape of the Earth. The French Academy decided to settle the controversy by carrying out measurements of the arc of the meridian at different latitudes.

Two such surveys were done between 1735 and 1748, and these surveys proved that the Earth was flattened at the poles and did bulge at the equator. These surveys removed the doubts created by Cassini who had challenged the mathematical concept of Newton and Huygens.