Episode 089 - Unusual Geological Phenomena - Springs That Change From Hot to Cold And Back Again
Date: 09/25/21
Link: https://www.epicureanfriends.com/thread/2203-episode-eighty-nine-unusual-geological-phenomena-springs-that-change-from-hot-to/
Summary
Section titled “Summary”The episode covers Book 6 lines 830–917. The panel concludes the previous episode’s discussion of Avernian places and falling birds, then examines Lucretius’s explanations of hot and cold springs — including the famous fountain at the temple of Jupiter Ammon, which Herodotus also describes as boiling at midnight. Martin notes that Lucretius dismisses an explanation that is actually correct and substitutes a wrong one involving seeds of fire being squeezed out when the earth contracts at night.
The episode also covers a cold spring said to ignite flax and re-light an extinguished torch (likely natural gas or an oil seep), freshwater springs welling up within the sea at Aradus (confirmed by Strabo), and the principle of action at a distance — leading into a brief introduction to magnetism and rings hanging in sequence from a magnet, which Lucretius announces will require extended treatment in the following section.
Transcript
Section titled “Transcript”Cassius:
Welcome to Episode 89 of Lucretius Today. I’m your host, Cassius, and together with my panelists from the EpicureanFriends.com Forum, we’ll walk you through the six books of Lucretius’ poem and we’ll discuss how Epicurean philosophy can apply to you today. We encourage you to study Epicurus for yourself and we suggest the best place to start is the book Epicurus and His Philosophy by Canadian Professor Norman DeWitt. For anyone who is not familiar with our podcast, please visit EpicureanFriends.com where you’ll find a friendly community with our goals and our ground rules clearly stated. If you have any questions about those, please be sure to contact us at the forum for more information. In this episode 89 we’ll read approximately Latin lines 830 through 917 from Book 6 as we discuss geological phenomena such as hot and cold springs that seem counterintuitive. Now let’s join Martin reading today’s text.
Martin:
Or else sometimes the force and rising blasts of these Avernian [places] dispel the air that lies between the birds and the earth, and the intermediate space becomes a void. Here, when birds are carried by their flight, they immediately flutter in the air, they clap their wings in vain, their pinions flag, and when they can no longer bear them up, nature must drive them down upon the earth with all their weight. And as they, hapless in the void of life, they breathe their soul abroad through every pore.
In some wells we find it cold in summer, because the earth is rarified by the sun’s heat, and by that means the seeds of fire it contains within break freely out into the air. And therefore the more the earth is affected by the heat, the colder the water will be that is closed within. But when the earth is contracted with the cold, when its surface grows close and its pores are stopped, this restraint hinders the heat from flying out. It is then squeezed together into the wells and the water becomes hot.
There is a fountain near the temple of Jupiter Ammon that is cold in the day and hot by night. Men strangely wonder at the quality of the spring and imagine that when the night has spread her dreadful darkness over the world, the water is warmed by the violent heat of the sun through the body of earth. But this reason is far from being true, for if the sun striking upon the open body of water is not able to warm even the surface of it, when it receives the force of his descending rays with all the heat, how can he warm the water and infuse his heat through so thick a body as the earth, especially since he is scarce able with his scorching beams to pierce through the walls of our houses?
What then is the reason? Doubtless this, because the earth near this fountain is more rare and spongy than it is in other places and contains within it many seeds of fire near the body of the water itself. Here, when the night has spread the world with the dewy shades, the earth below grows initially cold and is contracted. By this means it is compressed, as with your hand, and squeezes out those seeds of fire into the spring, which makes the water warm to feel and taste. But when the sun has driven away the night with its bright rays, and with its heat has rarefied the earth and made it loose, these seeds of fire return into their former place, and all the heat that warms the spring retires within the earth again, and so the fountain in the day is cold.
Besides, the water in the day is strongly removed by the sun’s ray, and by his teeming streams of heat, close rare, and so lets out the seeds of fire adhered by night, just as by the heat it shakes off seeds of cold and melts the ice and loosens all its bonds.
There’s likewise a cold spring over which if you place tow or flax it immediately takes fire and is all in a blaze. A torch newly extinguished in the same manner, gently drawn over the surface, is lighted by this water and flames out at every breath of air. And no wonder, for there are many seeds of fire in the water itself and many must needs rise out of the earth and ascend through all the fountains and flow abroad and make their way into the air; but yet they are not so hot as to set the spring on fire. Besides, the innate force of these seeds dispersed through the water compels them to move upwards and to unite upon the surface. As we see sometimes a fountain of sweet water bubble up in the middle of the sea and beat off the salt waves that are about it. The sea affords many of these springs that bring a seasonable relief to the thirsty mariners by throwing out streams of fresh water among the salt. The seeds of fire may in the same manner break through the water of this fountain and flow out into the torch. Here, when they unite and stick to the body of the torch, they immediately fall into a flame, where flax and tow contain many seeds of fire within, which makes them easily disposed to burn.
Do you not observe when you hold a candle newly extinguished to another that is alighted, it catches fire before it touches the flame? A torch likewise by that same rule will do the same, and many other things will take fire at a distance before the flame reaches it. And this, you may imagine, is the case of the fountain above mentioned.
And now I shall begin to show by what power of nature it is that the stone which the Greeks call a magnet from the country that produced it — what is found in the region of the Magnetes — has a virtue to attract iron. Men are amazed at the qualities of this stone. For it will make a chain of several little rings of iron without a link between, to hang together entirely from itself. You may sometimes see five or more hanging straight down and play in the gentle air, as they stick close and depend at the bottom one upon another. The ring that follows feels the attraction and power of the stone from that above it, so strongly is the virtue of the magnet communicated to the several rings. It acts with so great a force.
In inquiries of this nature many things are to be first proved before we can fix upon the true cause. He must trace subjects through many long and intricate difficulties. And therefore I beg you will hear me with a willing mind and with the closest attention.
Cassius:
Okay, thank you for reading that today Martin. This one’s a little bit shorter than we’ve been dealing with lately, but there are several changes of topic going on, and next week — or when we get to it — there’s a longer section on magnets. What we’ve included here at the end today will be just a teaser for some 200 lines devoted to magnets, as it says at the end. It’s a much more difficult subject to discuss. But for today we are continuing from last week, concluding the discussion of the Avernian pits or the Avernian areas that kill birds. So we’re not entirely departing from the dead bodies and the falling birds from last week. We can continue along that happy topic for a few more minutes anyway before we get to the rest of today. Anyway, again thank you Martin for reading that, and 830 is where we start today with the final words on those falling birds. Any comment on those? Don — I know that’s a favorite topic of yours.
Don:
Yeah, I will have to look some more information up about these falling birds and pits, and trees whose shade will kill you and all those sorts of things. That is an unexpected diversion there, it seems.
Cassius:
I think the funniest thing about today’s sections is he gets almost everything wrong. Well, let’s — before we go into the details of everything wrong and all the rest of it — I do have a comment, I guess, at the end of this line 830 about the falling birds. I guess what he’s adding in this passage is that they, helpless in the void, lie and then breathe their soul abroad through every pore. So perhaps this part of his discussion of the falling birds might be that one of the causes could be that maybe this pit has caused a vacuum or somehow removed the air, which allowed them to fall — but then there’s also the comment that they breathe their soul abroad through every pore. So we’re never very far from the observation that the soul is united with the body and at death is sent out into the world and dispersed just like with us. Distributed throughout the body, and so if it’s distributed throughout the body it’s going to leave the body through every pore as well.
Don:
Yeah. I think that’s at least sort of a transition from last week. And then we turn to this issue of how it’s apparently very interesting to him that there’s a fountain that can put out both cold and hot water at different times. I did find it interesting — in the Loeb edition at least — it talks about after line 839 that some editors think that there is a page missing from the archetype, from the original manuscript, and that’s the reason there’s such an abrupt break in topic there.
Cassius:
That’s a good point, because it sure is an abrupt break — it doesn’t have any transition whatsoever in what we’re looking at.
Don:
Yeah, so it looks like some editors think that there’s at least a page missing from the original manuscript, and that’s why there’s such a gap. But of course then in the Epicurean fashion, you know, some editors don’t think there’s a break there — so it could be this or it could be that.
Cassius:
Well, I guess we’d have to go back to the very beginning of Book 6 to look at the sort of topics that he was intending to cover, but we’re generally just going through a series of geological or just natural phenomena that strike people as unusual and showing what the natural solution for it is. Do you guys agree that that’s probably the general theme we’re doing here?
Don:
Yeah, I would agree. But definitely since he talks about how some people think that these Avernian locations are the entrance to the underworld and things like that.
Cassius:
Exactly.
Martin:
Yes, so basically in principle yes — but like I said, he gets the details in his explanations wrong. The only thing in his favor is that they’re all natural explanations.
Cassius:
Yes. You know, sometimes it surprises me when I think that you’re going to say something’s totally wrong and you say, well, it has some merit to some degree. So it’s hard for me sometimes to predict. How do we jump into it — do you want to talk in general about how you see something wrong about all of these, Martin, or do we just go through each one?
Martin:
Let’s go through the first first, because they’re quite different — each is quite different. So that Avernian area is apparently volcanic in origin. So possibly the area is hotter, and that means air which comes in from the side will rise. So the true thing is then the pressure of the air will go down. So the tendency toward the vacuum is not absolutely wrong. But actually birds like when this happens, because the draft of the air going up makes them rise easily — without that, they have to flap the wings. So they just sail and move up. I’ve seen this a lot: along a high-rise building here, the air tends to move strongly and often upward, and then the pigeons really like to fly up. Or recently when I sent them away, they lost a fairly big feather, and the feather itself was moving up.
Cassius:
Yeah, it is something to watch birds soar on those updrafts. We have a number of hawks and larger birds that are around this area, so it’s interesting to see them not even flapping their wings and just soaring in the sky.
Martin, now that you’ve brought that up, though, and I look at it closer — let me ask you this. Isn’t it interesting that he is seeing that the force and rising blast dispels the air? Well, I was looking for it to be stated specifically, and now I don’t see it — but isn’t he saying that because the intervening air becomes a void, that draws them in that direction? And that’s actually the principle of how an airplane flies, right? The wing displaces the air that goes on top, forces it to travel more quickly, and faster-traveling air has less pressure — and that’s how a wing rises, right?
Martin:
Yeah, I mean this is a simplified explanation. But the thing is, it’s not like this here. So in this case, the draft will not be strong enough to produce a real vacuum. In a real vacuum, yes, the birds would fall down — or if the pressure drop is extreme, yes, the birds would fall down. But they don’t do that. And also they wouldn’t really die if there was something like a stream of air pushing them down. So yes, they might try to steer against it, but it wouldn’t kill them. So there has to be some poisonous gases there which do kill them. And that’s why they come down and die.
Cassius:
Indulge me just a little bit further on this issue of the wings of airplanes, because it seems like I’ve read that there’s some controversy about whether in fact a wing gets its lift because the air traveling across the top has to go faster than the air on the bottom. I’ve heard there’s some controversy about that. But I guess what I am looking at here is he’s saying that the force of the pit dispels the air that lies between the birds and the earth, and the intermediate space becomes a void. So if indeed you have an area of air that is being forced in a particular direction to travel faster, that does create sort of a suction in that direction, right? Opposite — in the perpendicular direction.
Martin:
That’s Bernoulli’s law. So if you have a streaming fluid, the faster the stream is, the more you have some sort of a suction effect opposite to it. So that part exists, but there’s a counterexample — that this is the main reason for planes to fly — because planes can fly upside down.
Cassius:
Yes, yes. So you know what I’m talking about. I forget the Bernoulli name — I’ve read about that — but I guess when I was young and used to read Popular Science magazine or something, I would read about these issues. And yes, airplanes fly upside down even though supposedly if the air traveling over the curved side of the wing forces it in that direction, that would force the airplane down.
Martin:
Yes. Since this shows already, this is not the complete explanation. The complete explanation is more complex. I read an article on this which claims to have the proper explanation, but I forgot it now. Because the simple story with the Bernoulli law really sticks to the brain, and I really would need to dig up that paper to again figure out what’s the complete explanation for the flight of planes. But the Bernoulli effect has not been disproved — it’s still considered to be valid, at least to some degree.
Cassius:
It’s still part of it. The Bernoulli law is still part of the explanation, but it’s not as easy as it looks at first.
Okay. I love Martin’s line there — “the complete explanation is more complex.” I think that’s a good motto for something. I’m not sure what, but it’s a nice little retort to people who want nice, cut-and-dried answers sometimes. I mean, this is a good example, because I do remember when I was very young in school you would be taught about how an airplane flies, and there’d be pictures of these wings and the air would travel faster over the top — which would be the explanation for the curve of the wing. And then later I heard, well, that’s not true at all. So, like you said, it’s complex, and more than one thing going on at the same time. Okay, let’s move on. Go ahead.
Martin:
I mentioned he writes that in those textbooks, the drawn lines of how the air flows are completely invented. And I’m seeing how it goes in actual effect.
Cassius:
Well, I’m still not so sure that we shouldn’t peg this one, if we were looking for interesting scientific statements that presage the future — just like when he talks about how the feather and the rock would fall at the same speed in a vacuum. Maybe this is a statement that a thrusting area of air creates a suction of some kind. I don’t know whether that’s a good observation or not. But let’s move on to wells and how some are cold and some are hot. I think this is one of the ones you probably have a problem with too, Martin.
Martin:
The earth is porous. The phenomenon might be there — at least the way we feel it. This effect can be there. But in the later paragraph he dismisses the explanation which is actually close to what’s true, and his own explanation is wrong. So that is a quite interesting thing that those at the time had the right explanation already, and in this case Epicurus got it wrong.
Cassius:
Well, okay, so you said a couple things there. Does he come to a conclusion here as to which one he thinks is right, or is he simply still listing possibilities? You’re saying that maybe one of the first possibilities he lists turned out to be the right one, and he shouldn’t have gone any further — so you’re saying one of the ones he comes to you really don’t like?
Martin:
No, no. The thing is, he quotes an explanation which is not from Epicurus. It’s what some people think. And he dismisses that one — what other people say. But in this case, those other people are right. They have the right explanation, and Epicurus’ explanation is wrong.
Cassius:
Well, go ahead and lead us through that. What is the explanation that other people suggest?
Don:
Let me find this. Yeah, we can work our way through it. It looks like in 848, he’s talking about how some people say that the water is warmed by the heat of the sun through the body of the earth — as if it’s heated from the other side of the earth, I think. So he says that’s far from being true.
Martin:
Okay. Yeah. I wonder if you can imagine that when the night falls, the temperature shift is at least partial. So the thing is, there are still multiple ways to explain it. So one thing it could be is that it’s just subjective. What happens is, when the sun rises, the top surface of the earth gets heated up quickly — because, as he correctly says, the beams do not penetrate into it; they just stay at the surface, and that means the heat is deposited in a much thinner layer. Whereas in the water, the light penetrates very deeply, so that means there is almost no deposition of heat per volume in the water. So in this way the surrounding earth and the air above it get hot and the water is cool. So this is why in the daytime in summer the water is comparably cold, and then in the night the opposite happens. So the surface of the earth cools down very quickly after it’s no longer heated by the rays of the sun, and correspondingly the air is cool — and now the water, with its very large heat capacity, gives off its heat only very slowly. So subjectively you feel that the water is warm compared to what you feel above the cooled-down earth.
Cassius:
Now, Martin, it sounds to me like you’re sort of talking about large bodies of water, even including the ocean. Because I’m trying to decode this myself — it sounds like he’s really focusing on some wells and then he talks about a fountain. So is he really talking about large bodies of water or just a particular type of fountain that seems counterintuitive?
Martin:
Yeah, okay. But then it can still be explained from the earth, because another effect will also be in play. So from the surface of the earth, the heat will slowly travel deeper down to that portion which is in contact with the well, and then it will give off the heat to the water. And later, when night falls, the surface cools down quickly — but deeper down, because of the slow travel of heat through the rock, deeper down the rock is still hotter, still heated up, and then can give its heat to the water in the well. So I think this is an explanation which he dismisses, and that one is good.
Don:
I did find it interesting that the fountain or spring that he talks about with the shrine of Jupiter Ammon is mentioned both in Herodotus and in Pliny. So evidently this thing got some major airtime, as far as everybody knowing about it and being fascinated by it over a long period of time. And the general issue there, then, is just that it puts out cold water in the day and hot water at night.
Cassius:
Yeah, exactly. I pulled up the Herodotus section in his Histories, and it says — if you’ll indulge me for a second here — he’s talking about springs and salts and things like that in the desert: “The first on the journey from Thebes, ten days distant from there, are the Ammonians, who followed the worship of Zeus of Thebes — for, as I have said before, the image of Zeus at Thebes has the head of a ram. They have another spring of water besides, which is warm at dawn and colder at market time, and very cold at noon. And it is then that they water their gardens. As the day declines, the coldness abates; until at sunset the water grows warm. It becomes ever hotter and hotter until midnight, and then it boils and bubbles. After midnight, it becomes ever cooler until dawn. The spring is called the spring of the sun.”
So that is Herodotus. Not only is he saying that it’s hot at night, but it boils at midnight and then gets colder during the day. So it sounds almost like it’s like a hot spring, something with some sort of interval — like Old Faithful. Yellowstone.
Martin:
Yes. An interval. So it’s more something like that then — some interaction with geothermal effects. I had not seen that. That certainly didn’t come across in Lucretius, but that’s certainly what it sounds like when Herodotus is describing it. He’s going into much more detail there, it seems. But the funny thing is: where does this daily period of the geothermal activity come from?
Cassius:
Well, that’s what he’s saying in 861, it looks like. He’s saying that the heat of the sun is making the earth around the fountain more porous and that that somehow changes the heat of the area. The heat from the sun is sinking into the earth — is that what you’re saying?
Don:
Well, he says, “Doubtless this, because the earth near this fountain is more rare and spongy than it is in other places and contains within it the seeds of fire near the body of water itself. So then here when the night has spread the world with dewy shades, the earth below grows initially cold and is contracted, and by that means it is compressed and squeezes out the seeds of fire into the spring.” So he’s talking about temperature changes in the dirt around the fountain making it easier or harder for the heat from the surrounding area to touch the fountain apparently. That 861 seems to be the key, because then he says when the sun drives away the night and makes it loose, then the seeds of fire return to their former place and the heat that warmed the spring retires within the earth. So he’s talking as if the temperature changes during the day and night are compressing and decompressing the area around the fountain, allowing some kind of subterranean seeds of fire to seep into the water.
Martin:
I don’t think this has credibility. So the fact is that the geothermal effect is dominating. The only funny thing is — where does this daily rhythm of that dominating geothermal effect come from? So this one, as of now, I don’t want to speculate. Anything that the sun does there is too small in effect to account for things like that. So the reason for this daily fluctuation of the geothermal activity — that has to come from something else. Something really subtle. I’m sure that some geophysicist has examined this and has an explanation. I’m just not aware of it. So this one we may want to dig up to really get clear on.
Cassius:
Yeah, we used the word credibility there, and that calls to my mind that when I’m reading all this stuff there are really two levels of analysis. The first — even before I get to the question of whether I think he’s right or wrong — there’s always the first question: what is he saying? And this one, especially in 861 through 874, it’s kind of complicated to me to even understand what his position is, much less evaluate whether I think it’s right or wrong. Yeah, it almost seems like he’s saying that the sun is the source of all the heat for those changes in water temperature — but I would say he’s not saying that. I would say he’s saying that the sun is the source of the heat that changes what he calls, like, a sponge somewhere here. It looks to me like he’s saying that the sun’s heat is like it’s turning a valve on and off — or increasing or decreasing the porosity of the area around the fountain — and that whatever is underneath the fountain… It’s like he’s got some kind of analogy going where he’s squeezing or compressing a sponge and then letting it open and then it becomes more porous when you open it up. It reminds me of his metaphor for the fleece for the clouds — that the clouds soak up the water and then are squeezed going over different mountains, and that squeezes out the rain. So this, instead of the clouds as fleece, he’s using the earth as a sponge that squeezes and contracts and expands.
And there’s another word that, as you’re saying that, it reminds me of. It’s almost as if they’re really fascinated by this expanding and contracting analogy — because there’s that word about condensing pleasure, which I’ve never fully had a good explanation for what he means. But it’s almost as if there’s a lot of analogy going on through several places where there’s almost like a bellows effect or sponge effect — you’re pressing it together and then allowing it to expand. And for some reason that mechanism must have been of interest to them.
Martin:
I don’t think the sun can actuate this mechanism. Plus, it is not really clear what we should identify as the seeds of fire. So it just doesn’t make sense.
Cassius:
Right. Because it’s frustrating to me that he was talking about volcanoes for the longest time and the heat from the volcanoes and the sulfurous smells and that sort of thing, and that he can’t make the transition to the geothermal idea of heating up the water from maybe the lava or whatever it is that would possibly heat the water up. But it doesn’t seem like he can quite make that transition.
Don:
Yeah. It certainly seems like it would be related and he’d be talking about them at the same time. And maybe he is in his mind. Maybe that was in that missing page that the editors think was in the manuscript.
Cassius:
I thought it was nice that Herodotus at least gives some extra details on that spring or that fountain. That was kind of interesting.
Martin:
This was very important to mention, because it shows that my take was wrong. It’s important to know that because it’s silly if I am here stuck with the wrong explanation.
Don:
Yeah, and that’s one of the interesting things I find whenever the Loeb or some of the other translations give those notes — “this is also mentioned in Herodotus,” or “this is also mentioned in Pliny or Aristotle.” It’s always interesting to get those other takes on the source material that all the different authors were working from. The fact that this fountain is mentioned in Lucretius and Herodotus and Pliny — evidently everybody knew about this in the ancient world.
Martin:
Yes.
Cassius:
Let’s go ahead. I think similar issues occur throughout the rest of what we’re reading for today. Let’s talk about — so what’s the next example starting on 879? There’s a cold spring, and I meant to look up the word “tow” but I presume we’re talking about some kind of fabric or substance…
Don:
It’s like tow-headed. It’s like…
Cassius:
What does tow-headed mean? I’ve heard it — I’ve never known what it means.
Don:
I believe it’s blonde — somebody who’s blonde.
Cassius:
How does that relate to flax? Are we talking about a fabric?
Don:
Yellow. Fabric. Yeah, yellow.
Martin:
Yes, thank you. So when I look for the Brown translation, “tow” is identified as the same as flax, according to what I saw. I don’t know why it’s called that; I saw it identified as the same. According to our unimpeachable Wikipedia source, in the textile industry, a tow is a coarse broken fiber removed during processing flax, hemp, or jute.
Cassius:
Okay, and I see that both Munro and Bailey do not use “or” there, Martin — they just use the word tow. It must be that Mr. Brown’s translation thought that it would help us to have “tow or flax.” Maybe that’s basically parenthetical — so you can use that word.
Martin:
Yeah, maybe that is parenthetical.
Don:
And to answer your question — it says the very light color of flax tow is the source of the word “tow-headed,” meaning a person with naturally light blonde hair.
Cassius:
I had no idea. I thought it had something to do with being pointy-headed. So I’ve learned something today. I thought it was derogatory, in fact.
Don:
So tow-headed is not a derogatory term, you’re saying? No — someone with naturally light blonde hair.
Cassius:
Ah, wow. I think that’s why I’ve heard it mostly in relation to children — the young kids who have that really light blonde hair. Alright, so don’t listen to me on tow. So what are we talking about in 879 and 890? You’re placing a piece of flax over a cold spring and all of a sudden it blazes into flame? So we’re talking about some kind of natural gas or some other kind of liquid that’s semi-explosive or incendiary — is that what you think is going on?
Martin:
Oh, that won’t make sense on its own. You still have something that starts a fire and I just knew that’s where it could come from. So what kind of cold spring? Yeah, so it goes on with the torch, newly extinguished, in the same manner gently drawn over the surface and lighted by the water. So there you have an ignition source by that. And I mean, it could very well be either natural gas or some sort of oil or something — an oil slick that comes out of the ground, over the surface of water, over a spring or something like that. You could definitely see something like that happening with a torch.
Don:
Yeah. Natural gas or some sort of oil slick. Or methane.
Martin:
Yeah. That would work with a torch. So if you have a freshly extinguished torch, it is still hot. So that one can ignite the gas which comes out there. So that one is understandable. But not that you just place tow or flax there — this will not take fire without a source of ignition. Right.
Cassius:
I would agree with that. That seems to be expanding the analogy a little too much.
Martin:
Yes. So unless you have something — I mean, if you just have the flammable gas, it will not do that. So you need an oxidizer there which reacts immediately with the flax. I tried to figure out what should come out and be strongly oxidizing enough to do that. Currently I couldn’t think of anything natural which could do that.
Cassius:
So maybe he’s mainly just fascinated by the idea of there being a liquid that can burst into flame. But you’re right — the source of the ignition is a problem in what we’re reading here. But is it possible that that’s really what he’s concerned about — there’s something that looks like a liquid and yet it can… Do they have liquid sources of fire, alcohol? Does alcohol burn?
Don:
Oh yeah. Certainly they had alcohol.
Martin:
At a lower temperature. But yeah, you need to have high concentration. The alcohol from wine will not burn because it’s too low concentration. So you need — not sure whether they had distillation already. So if they were able to distill, to produce hot spirits, they can catch fire.
Cassius:
Yeah. I seem to remember paintings of Native Americans in western Pennsylvania around Titusville and those sorts of areas — where the first oil rigs were drilled — of, you know, Native Americans scooping up raw oil off the surface of water and streams and stuff that would leak out, and they would use that for various purposes. So that’s the kind of image I have in my head of this, with the torch and that sort of thing. Yeah, does that make sense?
Martin:
So that means a place where oil comes naturally to the surface — that makes more sense. It makes sense since he’s talking about Egypt and that sort of area too, where there’s a lot of oil. Sometimes the Sumerians, for example — they already had access to tar. They had tar on their roads. And they must have had something similar accessible to them.
Cassius:
Right, right. Okay, so he switches and discusses the sea at Aradus. He appears to be talking for a moment at least about fresh water flows within salt water areas. Now I guess that’s not particularly controversial, but then he goes back and talks about the tow further again. So I guess he’s using the Aradus freshwater flow example to show that you can have some other foreign substance welling up from below.
Martin:
But that is also what I question. Of course, depending on the geological conditions, you can have a spring of sweet water at the bottom of not-too-deep sea. If it’s too deep, you won’t have that. But if that area of the sea is shallow and the freshwater reservoir is above the level where the floor of the sea is, it will push the sweet water into the salt water. But I don’t think it will be undiluted enough that people on ships can just scoop up that water. By the time it reaches the surface, it would have been mixed with the salt water again.
Cassius:
Yeah, that would have to be a very shallow body of water and a really forceful spring coming up.
Martin:
Yes, it’s almost like really breaking through the surface of the sea there. Like a fountain. Okay, then you scoop that one up. But I’m not aware of anything like this happening. So what I’m aware of — you can have springs at the bottom, but not something that will make it to the top.
Cassius:
Well, now this is interesting. I just tried to find something about that spring at Aradus, and I’m seeing a thing from Science Direct saying — for example — the Roman geographer Strabo, who lived from 63 BC to 21 AD, mentioned a submarine fresh groundwater spring four kilometers from Latakia, Syria, near the Mediterranean island of Aradus. Water from this spring was collected from a boat using a lead funnel and leather tube and transported to the city as a source of fresh water.
Don:
Wow. So that’s pretty exact.
Cassius:
Yeah, that’s more sophisticated than an aqueduct by far, if they’re actually getting the water out of the ocean.
Martin:
Yeah. But like that, it makes sense, because if you bring a tube down to where the spring is, you can get it isolated enough from the salt water and get it out. So that might work. It’s quite ingenious.
Cassius:
I’ll try to find the section of Strabo and post that and maybe some other scientific things from that. Yeah.
Well, let’s cover the last two as an introduction to next week, because 906 and 917 are the introduction to magnetism. And I think Don’s already made the comment that 917 is a reference to — “in things of this kind, many points must be established before you can assign the true law of the thing in question. It must be approached by a very circuitous route. Wherefore all the more I call for an attentive ear and mind.” So he’s clearly talking about the complexity of certain issues, and this is going to be one of them.
Don:
As much as I like talking about those dead bodies, you’ve been wanting to talk about magnetism for some time.
Cassius:
That’s exactly right. This is all you, man. Well, I don’t have much expertise in it obviously either — any more than I have on tow-headed children apparently. I don’t know where Magnesia is or that area that it comes from. And all he’s really starting to say here is that you can produce five or more rings suspended in succession, tossing about in the air, each one in turn from the other experiencing the binding power of the stone. And with such a continued current its force flies through all. So how is he connecting this in his mind to the fountain at Aradus and the cold and hot fountain at Ammon?
Martin:
Like you mentioned, action at a distance. So the similarity is action at a distance.
Cassius:
Good point, yeah.
Martin:
At this point in the poem, it just remains empirical. So it just quotes the observation. I don’t see anything wrong in there — it sticks close to observation and doesn’t go too far. So that one is okay. But just back to paragraph 900 — taking out the wonder about catching fire at a distance: things which can burn, they will have a temperature at which, with the presence of oxygen, they will catch fire. And that is the explanation. So in order to ignite something, you don’t need it to be touched by a flame, as long as the temperature goes high enough — which, if you’re not too far away from the flame, is the case.
Cassius:
Yeah. I will say I find it somewhat heartwarming and very human to imagine somebody from, you know, 79 BC or whenever Lucretius was writing, talking about the rings hanging from a magnet and sort of swinging them in the air. It’s something that can fascinate people and children now. And it was just as fascinating hundreds and hundreds of years ago. So I just find that a very human sort of anecdote.
Martin:
I mean, it’s the only unusual action at a distance that we have in daily life. Say the magnet is something we may encounter in daily life. With most other things, it’s more complicated to do this — charge separation requires more effort. But the magnets are just there — you pick them up. And because this is the only thing, I mean, of course gravity is there too, but we are so accustomed to it that we take it for granted. It’s nothing special to us. But this magnet thing is something that normally doesn’t happen, and it’s unusually strong. At that moment, if we use the right parameters and sizes, it can counter gravity.
Cassius:
Yes. Countering the gravity part is very fascinating. All right. We are probably at the end of a normal session for today. So let’s think about wrapping up and closing thoughts. We turn to Martin.
Martin:
Yeah. So my comment on 900 was already my closing one, and the one on the magnet. So I have nothing additional.
Cassius:
Okay. Very good. Don.
Don:
I think I’m good. This was a fun little segment here.
Cassius:
Yes, it was. And I’m sad to say that next week you might not be with us. We’ll have to see what we want to do — if we have a substitute for you, or how we’ll cover magnets.
Don:
Someone will soldier on without me. Well, I don’t know about that. We’ll have to see. If we find somebody else who wants to talk about something, maybe we’ll take a detour. So we don’t want to deprive you of the ability to talk for 200 lines about magnets. I think we should make you read that section. You’ve been waiting for this for a while.
Cassius:
I don’t know about that. That’s right — this would be your turn to read next week too. So we’ll have to figure that out.
Don:
Clever of me now.
Cassius:
We’ll figure it out. And we have the 20th coming up tomorrow night for those who participate with us on the forum. That would be another opportunity to invite everyone who listens to the podcast — who might not take the time to come to the EpicureanFriends.com forum — to drop by and discuss this and all of our episodes with us and participate with us in studying Epicurean philosophy. We try to talk among each other not only on the podcast but at other opportunities when we get it. So everyone is welcome to drop by and we hope they will. So let’s close it at that, we’ll talk again in another week or so, and thank you again for your time today.
Martin:
Thank you.
Don:
Have a good day. Bye.