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Egyptian Circumnavigation of Africa ~600 BC

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Re: Egyptian Circumnavigation of Africa ~600 BC

#61

Post by mabbo »

> These men made a statement which I do not myself believe, though others may, to the effect that as they sailed on a westerly course round the southern end of Libya, they had the sun on their right - to northward of them.

It's 600BC. The idea that the world is a sphere isn't accepted yet. Herodotus explicitly says he doesn't believe what these sailors said- that the sun was to the north. Yet we know that if a sailor had done what is being described, this unbelievable fact would have been seen (and is regularly seen today by those living in the southern hemisphere).

If they didn't do it, where would this odd fact have even come from?

To me, that leads a lot of credence to the tale. Lots of challenges in the doing, but with the right experienced sailors not impossible at all.

Re: Egyptian Circumnavigation of Africa ~600 BC

#62

Post by pushswap »

foreigner wrote: post #28

If you haven't read it I highly recommend The History. Herodotus can be very entertaining. He pretty clearly lays out things he personally saw, things he heard from firsthand accounts, and things he heard secondhand. It's fun to see how things get more fanciful the farther you get away from the Mediterranean he knew. One thing that randomly sticks in my head is he said the Ethiopians were there most beautiful people…

Herodotus isn't considered reliable at all by historians in any of his writings whether his topic is close geographically or not.

Thucydides is a far better option , being at the beginning of the record for the continuous record of reliable historical writing.

Re: Egyptian Circumnavigation of Africa ~600 BC

#63

Post by wazoox »

fsckboy wrote: post #24

I'm skeptical. No matter how good the Phoenician sailors were, it seems unlikely to me that they could have blithely sailed past Cape Bojador[1] https://en.wikipedia.org/wiki/Cape_Bojador Maybe if they had small enough boats to stick close to the shore and portage. Seafaring on the Mediterranean is simply a lot less complex than it is on the open ocean. The European sailors were not able to pass this point till the 1…

Cape Bojador prevented travelling north to south for centuries, but south to north maybe not so much.

Re: Egyptian Circumnavigation of Africa ~600 BC

#64

Post by kragen »

lamp_book wrote: post #42
kragen wrote: post #23

Earlier quoted context omitted.

Eratosthenes calculated the diameter of the Earth pretty well in 00240 BCE. Aristotle claimed it was round around 00350 BCE, and might have had a correct value, but uncertainty about units of measurement means his error could have been as large as a factor of 2, and the roundness of the earth was still a matter of debate at the time. Herodotus died around 00425 BCE and probably wrote closer to 00435 BCE. They were al…

Yes, and there is a large chasm between discovery and information that is widely known and accepted among the population. For instance, many Europeans went with Ptolemy's less accurate calculation (made hundreds of years after Eratosthenes's) until the 16th century.

> there is a large chasm between discovery and information that is widely known and accepted among the population

There are even more extreme examples of this. The Moscow Papyrus is from 01850 BCE, and it explains how to calculate the area of a hemisphere from its diameter and how to calculate the volume of a truncated pyramid, so this information had already been discovered 3870 years ago—perhaps for many centuries.

Yet what fraction of people today know it? Try asking your taxi driver next time you're on vacation in Perú or the Philippines. Heck, I don't know the pyramid-volume thing myself! I'd have to work it out by integrating a quadratic.

(I recall that studying the calculus as a kid was a bit of a transition for me, because for the first time I came face to face with the realization that most adults' intellectual development was arrested around the year 01583 for some reason. It wasn't that they took a long time to grasp differentiation, or that they had some weird irrational belief at odds with reality, but that they just stopped learning and never grasped differentiation in the decades and decades they lived, converting themselves into intellectual dwarfs. I was still young enough to imagine that somehow I would avoid this...)

Re: Egyptian Circumnavigation of Africa ~600 BC

#65

Post by Hemospectrum »

sthnblllII wrote: post #58
estaseuropano wrote: post #50

Earlier quoted context omitted.

I'm currently reading Clive Pointing's 'World History - A new perspective'. >800 pages of well researched history with a large Eurasian focus (due to the availability of sources, not bias). He repeatedly makes the point that some technology that Europe 'discovered' in the 13-19hundreds was in fact known in china 1000+ years earlier. Most of recorded history Europe basically played no role whatsoever. A few examples t…

With all these advantages, why did the industrial revolution happen in Europe instead of Asia?

The industrial revolution was as much a product of economics as technology. If wages for lower-class workers hadn't been nearly so high, the technology might have come and gone without making much of a ripple. In fact, there's an argument to be made that it once did exactly that. Steam-powered machines were known to the Romans, and seen as a stupid novelty.

Disclaimer: I don't know English history well enough to put together a better explanation, but I'm sure this has been the subject of a number of PhD theses. Maybe someone can point to a source that goes into better detail.

Re: Egyptian Circumnavigation of Africa ~600 BC

#66

Post by w0de0 »

fsckboy wrote: post #24

I'm skeptical. No matter how good the Phoenician sailors were, it seems unlikely to me that they could have blithely sailed past Cape Bojador[1] https://en.wikipedia.org/wiki/Cape_Bojador Maybe if they had small enough boats to stick close to the shore and portage. Seafaring on the Mediterranean is simply a lot less complex than it is on the open ocean. The European sailors were not able to pass this point till the 1…

I'm trying to visualize the sailing conditions the Phoenicians would have faced at Bojador - and not really succeeding, because I don't know enough about their vessels.

But I'm sure the challenge would be different, and potentially less scary, from Henry the Navigator's bane. The Portuguese were in high-freeboard open-ocean sailing carracks, with no effective recourse to rowing. And Bojador, coming from the north, presents a terrifying lee shore: the winds and current push vessels towards it, with shoals extending from the coast. Sailing close to a lee shore is a bit like walking on a slack line: one mistake and disaster is inevitable. You need to accurately predict your drift over the whole transit, you need hope the wind doesn't veer, and because there's a ferocious current too, the wind must not die. In short, it takes a skilled captain and navigator (and the much better strategy is just to sail offshore, which is what the Portuguese eventually did). Even a modern Bermudan yacht would be challenged attempting to transit Bojador southerly and close to shore.

A Phoenician trireme-type-boat would not be able to sail upwind at all - rowing would have been required for this part of the journey. Maybe on a lull day they could out-row the current? In any case, the challenges were different - and they would have had the additional motivation of not being able to turn back for home.

[0] Source: I'm a sailor!

Footnotes so formatted are a shibboleth of this community, not a practicality.

Re: Egyptian Circumnavigation of Africa ~600 BC

#67

Post by tastyfreeze »

fsckboy wrote: post #48
tastyfreeze wrote: post #32

Earlier quoted context omitted.

Footnotes are useful to not break the flow of a thought with text that isn't meant to be read. Also, because of the link included at the end of a sentence, you were not able to include the conventional full stop immediately after the last character of the sentence.

we're going off topic here, but i always feel like comments like yours assume that I'm a complete idiot and don't know anything and need to be told something obvious :) what you say is so obvious, I'd prefer that you read your comment first as representing the generally held wisdom I'm arguing against, and then interpret my comment as a riposte to that. My point was that, and this applies to printed books also, what…

I made no assumptions of your competency. What I said was obvious to me but, your comment indicated that you didn't understand why people use footnotes on HN. To effectively communicate ideas to the largest number of people it is necessary to follow conventions. Bucking convention reduces your possible audience size.

Re: Egyptian Circumnavigation of Africa ~600 BC

#68

Post by ithkuil »

HDMI_Cable wrote: post #60
foreigner wrote: post #28

If you haven't read it I highly recommend The History. Herodotus can be very entertaining. He pretty clearly lays out things he personally saw, things he heard from firsthand accounts, and things he heard secondhand. It's fun to see how things get more fanciful the farther you get away from the Mediterranean he knew. One thing that randomly sticks in my head is he said the Ethiopians were there most beautiful people…

Wait the Ethiopians had coffee in 400BCE?

I remember having read the story that it originated a millennium later.

Re: Egyptian Circumnavigation of Africa ~600 BC

#69

Post by kragen »

detritus wrote: post #26
kragen wrote: post #23

Earlier quoted context omitted.

Eratosthenes calculated the diameter of the Earth pretty well in 00240 BCE. Aristotle claimed it was round around 00350 BCE, and might have had a correct value, but uncertainty about units of measurement means his error could have been as large as a factor of 2, and the roundness of the earth was still a matter of debate at the time. Herodotus died around 00425 BCE and probably wrote closer to 00435 BCE. They were al…

Mediterranean countries had artificial candle-or-whatever light with which to play upon spherical fruit dangling from trees, which otherwise in the daytime caught specular light glimmering through leaves. Knowing the Earth was round, I don't find it hard to imagine that interested minds of the day picked a fruit and toyed with it in hand, squinting a bit and considering the implications.

True, and surely some did—not just in the Mediterranean but in Perú and in Punt, and not just 2500 years ago but even a quarter million years ago—but, despite the whole lunar-eclipse thing, nobody had a really compelling argument until Eratosthenes precisely measured its curvature.

That is, though the wise could imagine a spherical Earth for as long as they have had fruit, they could just as easily imagine a non-spherical Earth. More easily, I think, because, I mean, look around you, it looks flat. It wasn't until Eratosthenes that the wise lost the ability to believe that the Earth was flat.

Re: Egyptian Circumnavigation of Africa ~600 BC

#70

Post by fsckboy »

sthnblllII wrote: post #58
estaseuropano wrote: post #50

Earlier quoted context omitted.

I'm currently reading Clive Pointing's 'World History - A new perspective'. >800 pages of well researched history with a large Eurasian focus (due to the availability of sources, not bias). He repeatedly makes the point that some technology that Europe 'discovered' in the 13-19hundreds was in fact known in china 1000+ years earlier. Most of recorded history Europe basically played no role whatsoever. A few examples t…

With all these advantages, why did the industrial revolution happen in Europe instead of Asia?

I'm no expert, but China has much, much less arable land than Europe. Something needs to finance industrialization, and in preindustrial times, food was finance because that's what supported a growing population.
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