Worldviews, Navigation, Exploration, and the Mali Empire in the Late Middle Ages

Technical Innovations in Navigation and Astronomy

• Heliocentric Astronomy and Planetary Motion:

  • In May 1543, Nicolaus Copernicus published De revolutionibus orbium coelestium, presenting a mathematical demonstration that planetary movements can be explained using a heliocentric worldview.
  • In 1609, Johannes Kepler published Astronomia Nova, introducing Kepler's First and Second Laws:
  • First Law: Planets move in elliptical orbits ($\text{Planeten in elliptischen Bahnen}$).
  • Second Law: A line segment joining a planet and the Sun sweeps out equal areas in equal intervals of time ($A_1 = A_2$ in equal durations).

• Navigational Astronomy and Geographic Latitude:

  • Ursa Minor (Polarstar / Polarstern): Used for navigation in Greek and Roman traditions since $600\text{ BC}$.
  • Geographic Latitude ($B$, latitudo, Lat, LAT): Defined as the angular distance in degrees ($0^\circ - 90^\circ$) north or south of the equator on the Earth's surface.
  • Astrolabe (Astrolabium): Instrument utilized to determine geographic latitude by measuring the angle of the Pole Star above the horizon.
  • Cross-Staff (Querstab / Jacobstab): Device operated by sliding a crossbar along a main shaft to measure angles and distances ($90^\circ$, $0^\circ - 90^\circ$).
  • Plumb Line / Weight (Lot / Gewicht an markierter Leine): Marked cord with a lead weight used for taking angular measurements or soundings.
  • Cartographic Developments: Evolution of Portolan charts (Portolankarte) and detailed star maps (Sternkarten, e.g., Edmond Halley, 1718).

Trade and Economic Motivations for Exploration

• Asian Luxury Trade in Europe (c. 1450):

  • For centuries, European trade with Asia involved luxury commodities including gemstones (Edelsteine), silk (Seide), dyes (Farbstoffe), and spices (Gewürze).
  • Genoa and Venice served as the primary European trade hubs, accumulating enormous wealth.

• Economic Power of Venice (1423 Data from Doge Mocenigo):

  • Population: $190{,}000$ inhabitants.
  • Annual Trade Turnover: $10\,\text{million Dukaten}$.
  • Annual Net Profit: $4\,\text{million Dukaten}$.
  • Maritime Workforce: $36{,}000$ active sailors on Venetian vessels and $16{,}000$ ship carpenters (Schiffszimmerleute).
  • Ordinary State Revenues: $1.1\,\text{million Dukaten}$.

• Merchant Networks and Sovereign Debt:

  • Italian merchants established commercial outposts across Spain, Portugal, England, and the Netherlands.
  • Capital loans provided to European monarchs for courtly expenses and military equipment left ruling princes financially dependent on merchant families.

• Ottoman Conquest and Mediterranean Trade Blockade:

  • In 1453, Ottoman forces conquered Constantinople and established control over the eastern Mediterranean and Black Sea coastlines.
  • The resulting Turkish trade monopoly and price controls made Asian goods virtually unaffordable across Western Europe, forcing a search for alternative sea routes.

The Portuguese Voyages of Discovery

• Initiative of Prince Henry the Navigator (1349–1460 / 1394–1460):

  • From 1420 onward, Prince Henry systematically dispatched vessels southward along the western coast of Africa to establish an ocean route to India, driving continuous improvements in navigation and shipbuilding.

• Expedition of Bartolomeu Dias (1486–1487):

  • Dispatched by the King of Portugal in 1486 with two $50\text{-ton}$ ships to locate the passage to India.
  • Departed at the end of August 1486, sailing south past the mouth of the Congo River down to latitude $29^\circ\text{ S}$.
  • Forced into open water by severe storms, navigating for 13 days with reefed sails.
  • After turning east and failing to find land, Dias steered north and reached a sheltered bay.
  • The exhausted crew, fearing starvation and the vast open ocean, refused to proceed further.
  • On the return voyage, the expedition sighted a prominent headland, which Dias named Kap der Stürme (Cape of Storms). King John II (König Johannes II.) subsequently renamed it Kap der guten Hoffnung (Cape of Good Hope).
  • Expedition Duration: 16 months and 17 days.

• Expedition of Vasco da Gama (1497–1498):

  • Conducted 11 years after Dias' return, navigating around Africa to reach India in 1498.
  • The outward journey to India required $317\text{ days}$.

Structural Layout and Logistics of the Exploration Caravel

• Internal Organization of the Caravel (Santa Maria Model):
  • 1: Admiralskajüte (Admiral's cabin)
  • 2: Steuerruder (Rudder)
  • 3: Kompass (Compass)
  • 4: Luke zum Schifffsladeraum (Hatchway to cargo hold)
  • 5: Entwässerungspumpe (Bilge/drainage pump)
  • 6: Hebevorrichtung für Anker und Segel (Winch/hoist for anchors and sails)
  • 7: Waffen- und Munitionskammer (Armory and ammunition room)
  • 8: geräucherte und getrocknete Fleischwaren (Smoked and dried meats)
  • 9: Schiffszwieback (Hardtack / ship's biscuits)
  • 10: Pökelfleisch in Fässern (Salted meat in barrels)
  • 11: Ölvorrat (Oil supplies)
  • 12: Wasservorrat (Freshwater supplies)
  • 13: Schiffsladeraum (Main cargo hold)
  • 14: Weinfässer (Wine barrels)
  • 15: getrocknete Hülsenfrüchte in Säcken, Zwiebeln und Knoblauch (Sacks of dried legumes, onions, and garlic)
  • 16: Mehlfässer (Flour barrels)
  • 17: Abstellkammer für Segel (Sail storage room)
  • 18: Laderaum für Taue (Rope hold)
  • 19: Sammelraum für Kondenswasser (Condensation collection sump)
  • 20: Steine als Ballast (Stone ballast)

Evolving Concepts of Time and Historical Consciousness

• Rural Experience of Time (14th and 15th Centuries):

  • Determined by natural agricultural cycles. Spring and autumn played minor roles, whereas summer and winter presented stark contrasts (summer equated to productivity, winter to cold, hunger, and disease).
  • Day and night formed a sharp duality: night symbolized danger and death, while day symbolized beauty (Schön wie der junge Tag).
  • Timekeeping was governed primarily by local church bells.

• Urban Timekeeping and Civic Structure:

  • Growing urban communities required precise scheduling. Town halls (Rathäuser) installed work bells ringing 24 equal hour intervals.
  • Cities maintained distinct local time systems; synchronization across regions was absent and unnecessary due to slow communication speeds.

• Perceptions of Past, Present, and Future:

  • Peasants: Maintained a cyclical view of time where major disasters (famines, plagues) were forgotten after a few generations.
  • Clergy: Viewed history lineally, anchored by the Birth of Christ as the central turning point. The secular world was seen as decaying until the Last Judgment (Jüngstes Gericht) and the fulfillment of the Kingdom of God.
  • Humanists: Formulated a tripartite historical division: Classical Antiquity, the uncultivated