Cortés Martin de Albacar

Background

Albacar was born in 1510, in Bujaraloz, Spain, the son of Martín Cortés and Martina de Albacar. Cortés belonged to an ancient and noble Aragon family.

Education

It is known that Albacar went to Cádiz University before 1530.

Career

The only other data on Albacar's life are those contained in his Breve compendio de la esfera, written in 1545 and reviewed by his contemporaries as possessing such order and clarity as to make it useful to those wishing to learn navigation. As the fever of discovery continued unabated into the beginning of the sixteenth century, so did the need for works that would expedite the navigation of unexplored oceans. In his letter offering the Breve compendio to Emperor Charles V, Cortés included this sentence: “. . . but I would rather call myself the first to have reduced navigation to a brief set of rules.” The Breve compendio consists of three parts: the first (twenty chapters) deals with the composition of the world and the universal principles of the art of navigation; the second (twenty chapters) considers the movements of the sun and moon and the effects they produce; and the third (fourteen chapters) deals with the construction and use of instruments and the rules of the art of navigation.

In his work, Cortés indicates that the earth has a torrid zone, two temperate zones, and two glacial zones. He describes how there is an atmosphere surrounding the waters of the sea, and in this atmosphere he distinguishes three regions: two hot ones at the extremes and a cold, dark, humid one in the center. He adds that on the earth - which is round, with mountains, valleys, and plains - the sea undergoes oscillations and swellings produced by the moon. The moon, according to him, is the smallest of the planets except for Mercury but appears large because it is near the earth. He subscribes to the Ptolemaic system of geocentricity and the immobility of the terraqueous globe at the center of the universe; he reasons that the earth is immobile, because a stone thrown into the air comes down on the same spot. He then describes the proper motions of the planets.

Cortés's Breve compendio is particularly concerned with practical navigation; a technological section includes rules for the construction and use of crossstaffs, astrolabes, and compasses. He is not satisfied with navigational charts that give only directions and distances (or polar coordinates) and says: “It is also necessary to know the latitudes of the principal headlands and of points and of famous cities.” He rejects maps with rectangularly drawn parallels and meridians and states that the farther a point is from the equator, the greater the separation of the parallels and meridians at that point. These ideas were the basis for the separation of the parallels in the cylindrical projection perfected subsequently by the cosmographer Alonso de Santa Cruz.

Cortes accepted Columbus’ discovery of the variation of magnetic declination (the declination of the compass to the northeast and northwest) and postulated the existence in the heavens of a magnetic pole. Cortes's achievement was to affirm the reality of this point when the existence of magnetic declination was still a matter of doubt; such a point explains precisely and clearly the declination of the compass to the northeast and northwest. Cortes drew upon these theories to account for the variation of magnetic declination at various places on the globe, attributed in other works of that period to the poor quality of magnets and lodestones.

Achievements

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  Cortés is best known for his navigational textbook, Arte de navigar (also known as Breve compendio). Upon its publication, the book was considered very important, particularly to the English. Indeed, the English translation went through six editions in the sixteenth century alone.

Works

More photos

• book

  • Breve compendio, Arte de navegar 1551

Connections

Father:

Martín Cortés

Mother:

Martina de Albacar

References

• Dictionary of Scientific Biography Volume 3
  1971
• Oxford Dictionary of National Biography The Oxford Dictionary of National Biography is a collection of 50,000 specially written biographies of men and women who have shaped all aspects of the British past, from the earliest times to the end of the year 2000, from the ancient (explorer Pytheas of the 4th Century BC) to the modern (Princess Diana).
  2004