New sailing / navigation inventions of the 1400s

Factual Questions
41

That is the premise thought—that’s why I said the inventions ‘made it possible’, not that they were the impetus for it. There were several discussions early in the thread about the causes of the exploration, but that was never the question.
I think the James Burke video explained it quite well though.

We know (or so all the books I read claim) that these inventions existed in the 15th century, but it’s always implied that they were fairly new, and I was trying to find out specifically what inventions are always being referred to.

42

And what I’m suggesting is that… perhaps the premise, whether as stated or as inferred, is flawed. That is, perhaps these inventions being referred to are really not all that new relative to the 15th century–that no such breakthrough occurred to spark the age of discovery in the 15th century and not sooner–but had all existed for hundreds of years, and that the people advancing such a narrative (implying that the 15th century became “the age of discovery” because of some relatively new technologies) have fallen into what seems a not uncommon trap of taking large swathes of time (hundreds of years) and reducing it down to something like “an age” together as if the developments were all essentially contemporaneous or as if the adoption of such technologies was necessarily uniform across cultures.

43

A map is useful, but an understanding of the wind and ocean currents that could be used to sail into the Atlantic AND get back again was probably more reassuring. They also had to avoid the areas where there were no convenient currents or winds and get stuck, becalmed and slowly starve or die of scurvy.

The seasonal nature of the prevailing wind direction was also new to them. Vasco de Gama discovered this to his cost between India and Africa.

Columbus went south to pick up the Canaries current and knew that if went north he could ride the Gulf stream and the prevailing winds to get back the Spain. This is the North Atlantic gyre.

The Portugese had discovered the Canaries and Portugal current in their expeditions following the coast of Africa.

They later discovered how to ride the trade winds of the South Atlantic gyre and execute the ‘Volto do mar’ and sale west then south to pick up the south westerly trade winds to south africa rather than getting wrecked on the African ‘Skeleton coast’. In so doing, they bumped into Brazil.

44

Nope. The Portuguese discovered quite a few Atlantic islands: the Azores, the Cape Verde Islands, the Savage Islands, and maybe Madeira, but the Canaries were known in antiquity.

45

Better ways of determining latitude, particularly in the Southern Hemisphere, evolved starting in the 15th century. From Wikipedia:

The mariner’s astrolabe which gives the angle of the Sun from the horizon at noon, or the angle of a known star at night, was used from around the 15th to the 17th century. The observation of the Sun instead of Polaris enabled the measurement of latitude in the Southern hemisphere but required the use of solar declination tables. One of the most famous tables, but certainly not the first one, was published in 1496 by the Castilian Jew Abraham Zacut, then exiled in Portugal.

So a combination of technology (an inclinometer) plus printing (published declination tables) made one of the key measurements of navigation possible.

46

These were not new technologies.

Astrolabes had been known since ancient times. They were standard instruments throughout the whole medieval period. The mariner’s astrolabe was in fact a simplified version of a normal astrolabe.

Likewise declination tables for the sun, moon, stars, and planets had been in common use everywhere for many centuries. Ptolemy’s Almagest was a well-known and comprehensive work on the subject published in the 2nd century.

The accurate determination of latitude was standard knowledge for any highly educated person. Astronomy was one of the subjects of the quadrivium, taught at medieval universities for a Master of Arts degree.

47

Yes?

I think a lot of people don’t know how big of an economic activity fishing was in the Middle Ages into the Renaissance, driven mainly by religious observance of frequent meatless days.

48

yeah its mostly to do with motivation , eg the motivation to risk the valuable galley , and ones life.
so the education of the navigator and expedition leader was one possible thing. every Med fisherman and navy guy knew that they getting stuck in parts of the Mediterranean was too easy … the ocean was just a big wild place … too dangerous, right ?

So it takes the wealth of Italy … then combine that with the educated and wealthy people of Italy who could visit Portugal, or employ Portugese sailors, so they could learn of sailing the coast of West Africa… The Portugese had been talking to the Canary Islanders for centuries, and slowly they had portugese speakers in the canary islands, and translaters who would translate west african fishermens knowledge to Portugese. They would hear how the fishermen could sail south to the cold… and compare that to Europe…sail a few weeks north, and its cold. So if its cold after sailing a few weeks south… then … thats not too harsh, its just a bit cold,not freezing. Its just general vague knowledge that gives them confidence.

I think the scientific knowledge of ocean currents may come from the strong ocean currents near Madagascar. The sailors going past there would have the strong ocean current slap them in the face and say “hey,you better study me !” and they learn the map of ocean currents is reliable … not just due to the prevailing wind, for example.

49

You are right. The history of the Canaries islands is ancient and complicated. It was fought over by the Spanish Castillians and the Portugese with stiff resistance to both from the local indigenous population.

These Atlantic islands were important staging posts for oceanic expeditions and learning how to use the winds and the currents to reliably connect with the mainland.

50

Not so much Italy, which did not exist as a nation state, but the Italian city states. The Republic of Genoa figures very significantly in expansion of the Iberian states into the Atlantic. Genoa was in serious competition with Pisa and especially the formidable naval power, Venice, in the Eastern Mediterranean as well as the expanding Ottoman empire.

Pushed out of the Eastern Mediterranean Genoa moved its attention to the West. They had banking, sailing and navigation expertise and were employed by the Iberian states to help expand into the Atlantic and along the African coast and North Africa.

Columbus was the most famous Genovese, employed by Spain. But there were many more that worked for the more advanced Portugese expeditions along the Atlantic coast of Africa for Henry the Navigator. Henry did not travel much himself, but he sponsored a series of expeditions using the best talent he could find. Genovese and Venetians had lots of experience from their maritime trading networks and colonies in the Mediterranean. They also had learnt how to set up banking systems. This was probably as big an innovation as any sailing or ship building expertise. Without the finance, ship building does not happen. It was an expensive undertaking and the newly unified Spain was short of money after a lot of expensive wars. The Genovese bankers got to bank and take a cut of much of the gold and silver the Spanish plundered from America. The Spanish came rather late to the exploration party, but got seriously lucky with Colombus.

They built ships based on what they knew of operating in the Mediterranean. The caravel could tack to make progress against an oncoming wind and had a rudder. It was small enough to be repaired on a beach, but it lacked the capacity to carry a lot of food and water for the crew. A major limitation was how long a ship and its crew could endure out of sight of land on the open ocean.

51

And more important to the investors, the capacity to carry treasure and trade goods.

52

I see what you’re getting at----I was thinking something similar when I wrote the question. The reason none of these books or articles ever mention specifics is perhaps because there aren’t really that many, and it’s just as you said above.

53

A key driver was Portugal’s Henry the Navigator who had the political and economic vision to finance expeditions to explore south along the coast of Africa. They were looking for trading opportunities and valuable stuff they could carry back to Portugal as well as route to India and China.

This went on for decades. These expeditions were the moonshots of their time.

As they went south into the tropics the came across kingdoms that had gold. They also came across sugar cane and established slave markets required by plantations. They transplanted this practice to the island of Madeira which had a suitable climate. Sugar was extremely valuable, white gold, in a Europe that had few sweet things. It became the template for a huge slave powered sugar processing business that was soon copied by the Spanish, Dutch, French and English. Mankind remains thoroughly addicted to sugar.

The Altantic coast of Africa was very hazardous until they worked out how to use the prevailing winds and currents and improve their technique which involved long detours into the Atlantic to pick up the trade winds.

There is an interesting parallel with the 20th century space race.

In the Cold War we had American and the Soviet Empires rattling sabres and racing to develop rocketry and an orbital launch capability.

In the 15th century we had the Western European states with Atlantic coasts cut off from the trade with Asia by the expanding Ottoman Empire that controlled the Eastern Mediterranean.

The states most affected by this were in the Iberian peninsular where they had been directly at war with Muslims in Spain and in 1492 managed to finally defeat the Caliphate of Cordoba and consolidate Spain from kingdoms into a unified Christian state.

Portugal had the advantage of being a unified state for much longer and under Henry had developed a response to the isolation from Asiatic trade routes. He used the most capable talent he could find and this developed into the worlds first global maritime trading empire.

He developed an oceanic thallocracy. An extension of the same concept that operated across the Mediterranean at different times by the Greeks, Phoneticians, Venetians, Genoese and others. His empire would be copied by the Spanish, Dutch, French and British.

No great invention, just a set of political and economic developments that drove innovation on the high seas to open up new trading networks.

What if there had been no block on trade by the expanding Ottomans and profiteering by the Italian city states. What if there had been some reconciliation between Spain and the Muslim states of Africa?

Who would venture into the wild Atlantic?

54

Even if there was just reconciliation between Spain and Portugal, desperate measures like sailing west for Asia would have been seen as unnecessary.