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Mathematician Pedro Nunes 100 Escudos Portugal Authentic Coin Money for Jewelry (Nonius) (Loxodrome) (Bimetallic)

Mathematician Pedro Nunes 100 Escudos Portugal Authentic Coin Money for Jewelry (Nonius) (Loxodrome) (Bimetallic)

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Mathematician Pedro Nunes 100 Escudos Portugal Authentic Coin Money for Jewelry (Nonius) (Loxodrome) (Bimetallic)

N.B. CONDITION - Circulated

Reverse: Pedro Nunes (1502-1578), a Portuguese mathematician, cosmographer, and professor, facing left
Lettering: PEDRO NUNES

Obverse: The arms of Portugal and the denomination below and the date at the bottom
Translation: Republic of Portugal
100 Escudos

Edge: Segmented in smooth and milled parts (different amount of segments)

Issuer Portugal
Period Third Republic (1974-date)
Type Standard circulation coin
Years 1989-2001
Value 100 Escudos (100 PTE)
Currency Escudo (1911-2001)
Composition Bimetallic: aluminium-bronze centre in copper-nickel ring
Weight 8.3 g
Diameter 25.5 mm
Thickness 2.5 mm
Shape Round
Technique Milled
Orientation Coin alignment ↑↓
Demonetized 28 February 2002
Number N# 1242
References KM# 645, Schön# 96

Pedro Nunes (Portuguese: [ˈpedɾu ˈnunɨʃ]; Latin: Petrus Nonius; 1502 – 11 August 1578) was a Portuguese mathematician, cosmographer, and professor, from a New Christian (of Jewish origin) family.

Considered one of the greatest mathematicians of his time, Nunes is best known for his contributions to the nautical sciences (navigation and cartography), which he approached, for the first time, in a mathematical way. He was the first to propose the idea of a loxodrome, and was the inventor of several measuring devices, including the nonius (from which Vernier scale was derived), named after his Latin surname.

Much of Nunes' work related to navigation. He was the first to understand why a ship maintaining a steady course would not travel along a great circle, the shortest path between two points on Earth, but would instead follow a spiral course, called a loxodrome. The later invention of logarithms allowed Leibniz to establish algebraic equations for the loxodrome. These lines —also called rhumb lines— maintain a fixed angle with the meridians. In other words, loxodromic curves are directly related to the construction of the Nunes connection —also called navigator connection.

In his Treaty defending the sea chart, Nunes argued that a nautical chart should have its parallels and meridians shown as straight lines. Yet he was unsure how to solve the problems that this caused: a situation that lasted until Mercator developed the projection bearing his name. The Mercator Projection is the system which is still used.

Nunes solved the problem of finding the day with the shortest twilight duration, for any given position, and its duration.

Nunes worked on several practical nautical problems concerning course correction as well as attempting to develop more accurate devices to determine a ship's position.

He created the nonius to improve the astrolabe's accuracy. This consisted of a number of concentric circles traced on the astrolabe and dividing each successive one with one fewer divisions than the adjacent outer circle. Thus the outermost quadrant would comprise 90° in 90 equal divisions, the next inner would have 89 divisions, the next 88 and so on. When an angle was measured, the circle and the division on which the alidade fell was noted. A table was then consulted to provide the exact measure.

The nonius was used by Tycho Brahe, who considered it too complex. The method inspired improved systems by Christopher Clavius and Jacob Curtius. These were eventually improved further by Pierre Vernier in 1631, which reduced the nonius to the Vernier scale that includes two scales, one of them fixed and the other movable. Vernier himself used to say that his invention was a perfected nonius and for a long time it was known as the “nonius”, even in France. In some languages, the Vernier scale is still named after Nunes, for example nonieskala in Swedish.

Pedro Nunes also worked on some mechanics problems, from a mathematical point of view.

Nunes was very influential internationally, e.g. on the work of John Dee and Edward Wright.


Coat of Arms of Portugal

At center, five escutcheon shields, forming a cross. On each shield are five round bezants (coins).

These five shields are arrayed in their cross on a larger shield. They are surrounded by seven golden, triple-towered castles.

Behind the shield, is an armillary sphere (which looks like a circle crossed by lines).

Present and past elements of the Coat of Arms of Portugal:

Quina (plural quinas) is the Portuguese term for a group of five things.

After the official recognition of the Kingdom of Portugal as an independent country in 1143 (it had been self declared as so in 1139), silver bezants were added to the blue cross of the shield, symbolising coins and the right of the monarch to issue currency, as leader of a sovereign state. Eventually, and given the enormous dynamism of medieval heraldry, it is believed that the shield degraded and lost some elements in battle, eventually losing the cross format. This is how King Sancho I inherited the shield from his father, Afonso Henriques, with the cross replaced by escutcheons with the silver bezants. A traditional legend explains that these escutcheons represent the five moor kings defeated by King Afonso I of Portugal in the battle of Ourique.

The number of silver bezants in each escutcheon varied extensively, with versions having represented from four up to eleven. In the late 14th century however, the number of bezants was fixed in five. Late explanations interpret them as the five wounds of Jesus Christ and/or the thirty pieces of silver (with the five bezants in the middle escutcheon counted twice), although this is highly improbable.

From the fixation of the number of bezants in five, the groups of the five escutcheons, each with five bezants of the Portuguese shield became popularly referred as quinas. By synecdoche, the term "Quinas" came to be used as an alternative designation of the coat of arms of Portugal and came even be used as a reference to anything that represents Portugal (e.g. the Flag of Portugal being often referred as the "Flag of the Quinas").

It was during the reign of Afonso III that the red bordure with golden castles (not towers, as some sources state) was added. Although the number of castles could vary between eight and twelve, Afonso IV would define them as twelve, and Sebastian I would finally fix them as seven. They supposedly represent the Moorish castles conquered by the Kingdom of Portugal during the Reconquista. Their origin is probably Castilian, but unlike Spanish castles, which usually have their gates coloured blue (hence opened), Portuguese castles were usually depicted with gold gates (hence closed). As a matter of fact, Afonso III was the second son of King Afonso II of Portugal and thus was not expected to inherit the throne, which was destined to go to his elder brother King Sancho II of Portugal. As a second son, the coat of arms of Afonso III included both the arms of his father and the arms of his mother Urraca of Castile, thus the Castillan red border with golden castillan castles, around the Portuguese shield inherited from his father.

Armillary sphere
An important element of Portuguese heraldry since the 15th century, the armillary sphere was many times used in Portuguese naval and colonial flags, mainly in Brazil. It was a navigation instrument used to calculate distances and represents the importance of Portugal during the Age of Discovery, as well as the vastness of its colonial empire when the First Republic was implemented.

Although it is commonly regarded as a "republican" element, as opposed to the monarchist crown in the blue/white flag (see Flag of Portugal), its usage predates the republic by several centuries; it was the personal emblem of Manuel I. Some flags of the monarchic era, such as the flag of the United Kingdom of Portugal, Brazil and the Algarves, already depicted armillary spheres. The incorporation of the armillary sphere into the 1816 flag of the United Kingdom of Portugal, Brazil and Algarves is related to the adoption of the first flag of the Kingdom of Brazil, an armillary sphere on a blue background.

The coat of arms sported different crowns during imperial rule of Portuguese and foreign crowns.

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