Speaker 1: Welcome to Stuff to Blow Your Mind, the production of
Speaker 1: My Heart Radio. Hey, welcome to Stuff to Blow Your Mind.
Speaker 1: My name is Robert Lamb and I'm Joe McCormick, and
Speaker 1: we're back with part two. In the last episode, we
Speaker 1: talked about the settlement, the original colonization of the Pacific Islands,
Speaker 1: and today we're back to talk about some documentation of
Speaker 1: the amazing navigation techniques used by the master navigators of
Speaker 1: various Pacific islands. Uh. And I'm really excited to talk
Speaker 1: about this stuff today because I've been reading this big,
Speaker 1: very important book on the subject that was published in
Speaker 1: nineteen seventy two by an author named David Lewis called
Speaker 1: We the Navigators that involves extensive interviews with and then
Speaker 1: direct sailing in firsthand observation of the navigation techniques of
Speaker 1: master navigators from the Pacific Islands, for example, a man
Speaker 1: named Tevak of the Santa Cruz Reef Islands and a
Speaker 1: man named hip Or of Poula Wat in the Carolines.
Speaker 1: And today we're gonna be talking about some of these
Speaker 1: specific navigation techniques. Yeah. And again these are the techniques
Speaker 1: of environmental navigation, so navigation at sea on the open sea,
Speaker 1: conducted without instruments. Uh and and so I mean that's
Speaker 1: ultimately the really amazing part of this. But then at
Speaker 1: the same same time, I want to stress something we've
Speaker 1: mentioned in the first episode that this is also not
Speaker 1: based in sort of a gut instinct, a kind of
Speaker 1: well I've been at sea enough, I kind of know
Speaker 1: what I'm doing. No, this is a this is a science.
Speaker 1: This is this is these are techniques that would have
Speaker 1: that were passed down from generation to generation, from skilled
Speaker 1: individual to two skilled individual. And uh. And so you know,
Speaker 1: we see this continued on in oral traditions, but then
Speaker 1: also we've seen them recorded, especially in the last few decades.
Speaker 1: Uh that there's been a resurgence of interest in this
Speaker 1: uh an effort to to make sure that these traditions
Speaker 1: and techniques survived and then also to use them to
Speaker 1: understand the history of the colonization of these islands by
Speaker 1: ancient humans. Right. And one of the points that Lewis
Speaker 1: argues in his book is that the colonization of the
Speaker 1: islands of the Pacific was not driven entirely by random drifts, say,
Speaker 1: people getting blown off course by a storm or getting
Speaker 1: lost and then happening upon a new island. That that instead,
Speaker 1: he argues that a lot of these islands were probably
Speaker 1: discovered by deliberate exploratory probes. Right, so let's get into
Speaker 1: some of the techniques. Then. We're going to start with
Speaker 1: what may seem the most obvious, and that is the stars.
Speaker 1: There are a lot of amazing techniques to talk about,
Speaker 1: but this is by far the most important one. Yes,
Speaker 1: so Pacific islanders. Uh, specifically the trained navigators, they did
Speaker 1: use the stars. The train navigator knew the positions of
Speaker 1: important stars and their relationship to islands by heart. They
Speaker 1: knew how the pattern of the stars changed depending on
Speaker 1: where you went and what time of the year it was.
Speaker 1: And they could also use the stars to determine latitude,
Speaker 1: so it's your north south positioning. They could roughly determine
Speaker 1: where they were in relation to the equator based on
Speaker 1: the height of Polaris or the southern cross above the horizon,
Speaker 1: which they would measure, again not using instruments, but using
Speaker 1: the human hand. Yes, or sometimes I think also maybe uh,
Speaker 1: parts of the boat could be used to sort of
Speaker 1: orient with the stars on the horizon. Right, So, if
Speaker 1: you're unfamiliar with this, kind of technique. As obviously most
Speaker 1: of us are as I am, the mind is immediately boggled, right,
Speaker 1: you think, Okay, how would I use the stars to
Speaker 1: find I don't know a city or something like that. Uh,
Speaker 1: you don't. You wouldn't even know where to start. But
Speaker 1: once you know to look for, this actually becomes an
Speaker 1: extremely reliable method. Uh. And specifically, the really important guide
Speaker 1: stars here are constellations that are low in the sky
Speaker 1: around the point where they are either rising or setting,
Speaker 1: and can be easily associated with a particular heading toward
Speaker 1: the horizon. So you're steering your boat and you're observing
Speaker 1: the stars right around the horizon. So these would be
Speaker 1: either stars and star constellations that have recently risen or
Speaker 1: are about to set, depending on which direction east west
Speaker 1: you're heading. So if you have a particular destination in
Speaker 1: mind and you know you're starting position, you can associate
Speaker 1: your destination with a particular guide star. Or what a
Speaker 1: guide star would actually mean is a series of stars
Speaker 1: and star constellations that will move move vertically up and
Speaker 1: down across the sky as the night goes on. But
Speaker 1: they might be identified by say the first star. You
Speaker 1: would see the sequences as the guide star, and then
Speaker 1: the train of subsequent stars that would move up and
Speaker 1: down as the night goes on. But that is associated
Speaker 1: with a particular island. Now, of course, it gets much
Speaker 1: more complicated than that, because, for one thing, you have
Speaker 1: to take into account position and geography, because while a
Speaker 1: star can help give you a heading toward a known
Speaker 1: island that's associated with it would only necessarily be associated
Speaker 1: with the island you're heading for from a particular direction. Right,
Speaker 1: So if you're heading from east to west, the island
Speaker 1: you're looking for is under a certain star, but if
Speaker 1: you're heading from north to the same island, that island
Speaker 1: would be under a different star. Right. So the stars
Speaker 1: help you get an orientation, but you have to know
Speaker 1: the relationships between a sort of mental map of islands
Speaker 1: in your head and how shifting the starting point of
Speaker 1: the journey will shift what star path will lead you
Speaker 1: to your island destination. But it gets even more complicated
Speaker 1: than that because, of course, as we mentioned, the stars
Speaker 1: don't stay still throughout the night. The earth is rotating,
Speaker 1: so the fixed stars rise and set across the sky
Speaker 1: over the course of a night, and as the stars
Speaker 1: rise higher or set below the horizon, they become less
Speaker 1: useful or not useful at all for navigating without equipment
Speaker 1: and charts, not just because say, they're higher as they're
Speaker 1: rising up, but also because they tend to rise at
Speaker 1: an angle, so they won't stay right where they're supposed
Speaker 1: to be on the horizon. What you want is a
Speaker 1: reference star that is either just rising if you're heading east,
Speaker 1: or is just about to set if you're heading west. Um,
Speaker 1: So what do you do there? Well, what you would
Speaker 1: tend to do is cycle through new sets of rising
Speaker 1: or falling guide stars that you know will keep you
Speaker 1: pointed in the right direction. And Lewis writes about this
Speaker 1: that on average, you won't need more than about ten
Speaker 1: guide stars to sail through an entire night, given the
Speaker 1: amount of time that each star is usually pretty close
Speaker 1: to the horizon, close enough to be usable. So you
Speaker 1: can almost imagine kind of a I don't know, like
Speaker 1: those like stock ticker strips, you know, the old one
Speaker 1: is like a strip of stars that are peeling up
Speaker 1: over the horizon all night long, and each one, you know,
Speaker 1: is the next one in the set that is still
Speaker 1: oriented with the top star in that strip that will
Speaker 1: keep you going in the direction you need to go,
Speaker 1: But stop and think about, like how much memorization this requires,
Speaker 1: Like how much you need to know about what the
Speaker 1: stars look like, what their orientations are, and their relationships
Speaker 1: to the islands you need to get to, depending on
Speaker 1: where you're starting point. Is So the amount of navigational
Speaker 1: lore that needs to be committed to memory and the
Speaker 1: amount of detail in it is is absolutely astounding. I mean,
Speaker 1: it reminds me a little. These are not directly comparable
Speaker 1: at all, but it reminds me a little of how
Speaker 1: in or is it Mark Twain's life on the Mississippi
Speaker 1: talking about how an experienced riverboat pilot would need to
Speaker 1: know by heart the entire river, like all the various
Speaker 1: details of its it's twist and bends, its depth, et cetera,
Speaker 1: and everything that went into knowing it. Which, um, yeah,
Speaker 1: from what I've read, you can you can basically take
Speaker 1: that and apply it to to any kind of nautical setting,
Speaker 1: and certainly this one is well. Like you would need
Speaker 1: to to know by heart the environment through which you
Speaker 1: would be uh sailing, the environment of the waters, but
Speaker 1: also the environment of the stars above. Yeah, And it
Speaker 1: seems that while I don't know, while the mental memorization
Speaker 1: of physical surroundings on land, including like trees and changes
Speaker 1: in terrain and rocks and landmarks and stuff like that.
Speaker 1: It maybe this is just my land lubb or bias,
Speaker 1: but it seems like that kind of thing probably comes
Speaker 1: more intuitively. It's more just sort of like a biological
Speaker 1: default to recognize landmarks like plants and rocks and stuff
Speaker 1: like that. Then it would be to memorize the stars
Speaker 1: as your landmarks for guidance. Yeah, yeah, I think you're right.
Speaker 1: I mean, it almost feels like sailing through the space. Uh.
Speaker 1: Though of course there's going to be plenty concerning the
Speaker 1: water itself and the and uh and other environmental cues
Speaker 1: that will get to But but certainly at this point
Speaker 1: in the in the podcast, it's easy to to almost
Speaker 1: think of these as space voyages because of the degree
Speaker 1: of focus that must be placed on the stars, right,
Speaker 1: and so experienced specific navigators can use these rising and
Speaker 1: setting guide stars to form this extremely accurate mental compass.
Speaker 1: Lewis gives one example of one of his voyages with
Speaker 1: the navigator TVAK, and he says, quote, by these obliquely
Speaker 1: sinking stars, he was able to inform me that during
Speaker 1: the evening that the wind had backed from southeast to
Speaker 1: south southeast. I seriously doubted the accuracy of his observation
Speaker 1: until Canopus, topping the horizon on a bearing of a
Speaker 1: hundred and forty three degrees exactly in line with our stern,
Speaker 1: confirmed that we were in fact dead on course and
Speaker 1: that the wind had changed. Now, there's another variation on
Speaker 1: idea of guide stars for navigation that is known as
Speaker 1: the sidereal compass. That is basically like a a view
Speaker 1: of the night sky that identifies particular rising or setting
Speaker 1: stars with points on an imagined compass. Again, this is
Speaker 1: not a piece of equipment, an external tool. This is
Speaker 1: a compass in the brain that has a picture a
Speaker 1: mental map of the stars and how the stars along
Speaker 1: the horizon will give you information about north, southeast, and west. Now,
Speaker 1: these are the basic primary methods of navigation by stars,
Speaker 1: but obviously in practice it's a lot more complicated, So
Speaker 1: a few examples. Of course, there is a lot of
Speaker 1: adjusting the course to compensate for variations and currents and winds,
Speaker 1: and to be adaptable for for celestial orientation markers. When
Speaker 1: part of the sky is obscured, for example by clouds,
Speaker 1: and I'll mention more about that in a minute. There's
Speaker 1: another thing that's a complication with the use of guide
Speaker 1: stars for navigation, which is the seasonality of guide stars. Uh. Now,
Speaker 1: of course, the availability of guide stars varies with the seasons,
Speaker 1: because the sidereal day is actually twenty three hours and
Speaker 1: fifty six minutes long, not twenty four hours. So each
Speaker 1: star rises and sets four minutes earlier each night. And
Speaker 1: as you can imagine, as this builds up over time,
Speaker 1: you're actually going to be having different star maps available
Speaker 1: to you as the year goes on. So in illustrating this,
Speaker 1: Lewis writes that quote Tevak told me that the sailing
Speaker 1: season in the Santa Cruz group lasted all year round,
Speaker 1: and that there were appropriate steering stars for each time
Speaker 1: of year. Similarly, when two two indicated the stars for
Speaker 1: the Nomuka Tonga Tapoo passage, he stressed that the ones
Speaker 1: he was showing me were usable only up to about September,
Speaker 1: after which new stars and sailing directions had to be used.
Speaker 1: So not only do you have to understand this whole
Speaker 1: star map and its relations and ship to the island geography,
Speaker 1: but also if you if you're sailing across different seasons,
Speaker 1: you have to have the seasonal backups in mind as well.
Speaker 1: Then there's even more to to take into account. One thing,
Speaker 1: for example, is wind and leeway, So experience navigators will
Speaker 1: have a mental map to reach their destination that must
Speaker 1: include compensation for leeway. You know, the sideward drift of
Speaker 1: a boat as it is is blown sort of off
Speaker 1: course by wind. So if the navigator knows that the
Speaker 1: destination is under a particular star, but there is a
Speaker 1: known and relatively dependable amount of southerly drift on the
Speaker 1: journey due to prevailing winds and currents, they actually have
Speaker 1: to aim a certain amount north of the guide star.
Speaker 1: That makes sense, Yeah, and that's just for permanent drifts.
Speaker 1: There's also sort of more ad hoc compensation that has
Speaker 1: to take place along the way as well. But one
Speaker 1: of the big things that that really struck me about
Speaker 1: this was how how much it inverts the logic of
Speaker 1: nighttime now vigation versus daytime navigation. You know, uh, well, like,
Speaker 1: how how would you think, what do you think would
Speaker 1: be the best time to try to get somewhere. Obviously
Speaker 1: you would probably think it's in the day, right when
Speaker 1: you can see where you need to go. But it
Speaker 1: is much easier to use the highly dependable celestial navigation
Speaker 1: techniques of of the Pacific Islander navigation lore at night
Speaker 1: than it is in the daytime. There there's still tools
Speaker 1: they use in the daytime, and I'll talk about those
Speaker 1: in a minute. Um. But even when the stars are
Speaker 1: largely obscured by clouds, an experience navigator can usually use
Speaker 1: some stars in the sky to orient and to get
Speaker 1: onto the correct bearing, for example, by noting which stars
Speaker 1: might lie it's a nine d degrees to the course, etcetera. Yeah,
Speaker 1: I mean it almost sounds like you would you would
Speaker 1: probably want to leave the shore, you know, around dusk,
Speaker 1: um and uh, and then once and then hopefully you're
Speaker 1: you're out to see by the time the stars have
Speaker 1: come out. Right. Well, there's actually there's a good bit
Speaker 1: of thought about when are the best times to arrive
Speaker 1: and depart. So they talked about, Yeah, I think it's
Speaker 1: usually customary to leave during the daytime. And one of
Speaker 1: the main reasons it's important to leave during the daytime
Speaker 1: is uh, not only that people can be notified and
Speaker 1: you can say prepare things to take along with you.
Speaker 1: That same day like fresh food, and you can say
Speaker 1: your farewells to people during the daytime, but you can
Speaker 1: also look back at the island you're leaving from to
Speaker 1: get back bearings, right, So you can make use of
Speaker 1: of the land for your navigation for as long as
Speaker 1: it's feasible. Right. And it's also usually considered important to
Speaker 1: arrive at your destination during the daytime because one of
Speaker 1: the great perils actually of Pacific navigation is accidentally missing
Speaker 1: your target in the dark. If you sail past the
Speaker 1: island in the dark and you don't realize you've done it,
Speaker 1: that can be uh that that could be a death sentence.
Speaker 1: So it's kind of interesting while you're out on the
Speaker 1: open ocean, navigating at night is ideal. That's you know,
Speaker 1: where you get these accurate guide stars. But I think
Speaker 1: it's often considered good to leave the island during the
Speaker 1: daytime and to arrive at your destination during the daytime
Speaker 1: and sometimes uh and there might be some exceptions to that,
Speaker 1: but those seemed to be some general principles that were
Speaker 1: observed at least that Lewis mentioned and uh and so
Speaker 1: that would require very careful timing of the journey, right,
Speaker 1: Like you need to know pretty much exactly how long
Speaker 1: it's going to take, how many days, so that you
Speaker 1: can time it out like that. And just as one
Speaker 1: example about the dangers of missing an island at night,
Speaker 1: uh Lewis talks about at least one of the navigators
Speaker 1: he worked with having a practice of when you're getting
Speaker 1: close to the island and it's really dark out, sometimes
Speaker 1: they would just stop sailing. They would slow down. They
Speaker 1: would uh it's called heaving to, you know, they would
Speaker 1: heave to to slow the progress of the boat, just
Speaker 1: to be super careful that they didn't accidentally, say, sail
Speaker 1: between two islands unnoticed in the middle of the night.
Speaker 1: But while the nighttime star navigation is the most accurate
Speaker 1: thing to use, there are clues you can use for
Speaker 1: navigation in the daytime as well. For example, you can
Speaker 1: use the sun. It's more difficult to use the sun,
Speaker 1: but it can be done. Uh. And it's more difficult
Speaker 1: for a number of reasons. First of all, there's only
Speaker 1: one of it, and its position can vary a lot
Speaker 1: over the seasons. Right. Unlike the stars, the relative position
Speaker 1: of the Sun on the horizon of Earth has a
Speaker 1: lot more variability. But even with the seasonal variability of
Speaker 1: the sun's position, you can still use it to navigate
Speaker 1: by pairing it with external reference to the stars. And
Speaker 1: this was one of the many moments in this book.
Speaker 1: It gave me that like, oh, of course kind of feeling,
Speaker 1: and this was one of them. So uh So, Lewis
Speaker 1: writes at one point about another scholar who had been
Speaker 1: writing about Pacific navigation uh named Aker Blom. He says,
Speaker 1: quote Aker Blom surprisingly asserts that to achieve a satisfactory
Speaker 1: degree of accuracy when checking the course by means of
Speaker 1: the bearing of the rising or setting sun, the Polynesian
Speaker 1: navigator must necessarily have had access to some form of
Speaker 1: memorized table of the changes in the sun's asimuth. So
Speaker 1: it's you know, changes in rising and setting patterns over
Speaker 1: the seasons. But contrary to that, Lewis says, all the
Speaker 1: navigator actually needs, of course, are his eyes and a
Speaker 1: knowledge of the stars. The sun star comparison could be
Speaker 1: made twice in each day if one were so minded.
Speaker 1: So when the sun is rising or setting, you can
Speaker 1: check its orientation with respect to the stars that appear,
Speaker 1: you know, before or after it, and then you can
Speaker 1: basically know where on the horizon it is rising or
Speaker 1: setting at this time of year. Wow. Yeah, thank Now
Speaker 1: there are other methods of maintaining course setting during the
Speaker 1: daytime that are again more difficult than the nighttime, but
Speaker 1: still possible. And another method that I thought was really
Speaker 1: interesting was steering by ocean swells. And they're actually two
Speaker 1: different uses here. Um, So there's one thing, which is
Speaker 1: navigation by swells in the open water. So if you're
Speaker 1: out you know, no side of land anywhere nearby, you
Speaker 1: can use ocean swells to help you do direction finding,
Speaker 1: just like you would use the sun or the stars.
Speaker 1: But in addition to that, using the swells is actually
Speaker 1: a land finding technique. It changes in how the ocean
Speaker 1: swells are affected by nearby land masses can be used
Speaker 1: to locate islands that are nearby, and this is something
Speaker 1: we'll probably talk about more in the next part of
Speaker 1: this of this series. But what does it mean to
Speaker 1: steer by swells in the daytime? Well, swells are permanent
Speaker 1: wave patterns with specific cardinal origin points, which are associated
Speaker 1: not with waves kicked up by transient weather, but with
Speaker 1: strong and persistent wind patterns associated with specific permanent weather systems.
Speaker 1: For example, the trade winds or what or what a
Speaker 1: Louis calls the southern Ocean belt of strong westerly's. Yeah,
Speaker 1: and I think we can sort of loosely imagine like
Speaker 1: a recreation of a basic form of this, you know,
Speaker 1: in some sort of a model or simulation, if you
Speaker 1: had a body of water and you had to say
Speaker 1: a fan or something creating some sort of you know,
Speaker 1: of disturbance across the surface, and it it was regular,
Speaker 1: what would happen if you then dropped some islands in there?
Speaker 1: It could disrupt the waves, especially in if we were
Speaker 1: talking in in the actual ocean, in the form of
Speaker 1: long ocean waves as they bend around land masses. And
Speaker 1: and this wave disruption can be identified by a skilled eye,
Speaker 1: enabling them to detect land hundreds of kilometers wave, and
Speaker 1: which is is pretty amazing, right, And so that's the
Speaker 1: kind that would be used specifically for the land finding, right.
Speaker 1: But you can also use the ce swells like you
Speaker 1: would use the stars to get directional orientation to know
Speaker 1: which direction is north, southeast or west without a compass,
Speaker 1: Because if you know basically what direction c swell that
Speaker 1: is permanent and reliable comes from, you can detect that
Speaker 1: swell and then no, okay, that way is south southeast. Right.
Speaker 1: So so now we have not only the stars above,
Speaker 1: but also uh, the wave patterns the c swells as well. Right,
Speaker 1: So these permanent weather patterns, they originate in a fairly
Speaker 1: consistent direction from your location. Now, part of the ignorant
Speaker 1: land dweller in me is just incredulous here, right, Like
Speaker 1: when I'm out in a boat on the ocean, waves
Speaker 1: seem utterly random to me. I could not I could
Speaker 1: not identify that waves are coming from a particular direction.
Speaker 1: And you know, but they're not well, unless it's coming
Speaker 1: from a ski do right, then you are motor boat
Speaker 1: that's coming by then it's pretty clear what's creating the distraction.
Speaker 1: That's a good point. But you know, just the general
Speaker 1: choppy wave patterns of the ocean, I wouldn't have any
Speaker 1: idea what to do. But if you are trained in
Speaker 1: knowing what to look for, you actually can identify particular
Speaker 1: wave patterns or swell patterns. Lou actually makes a distinction
Speaker 1: between waves and swells. Um. But but they're not just random.
Speaker 1: The system of orientation based on swells is not as
Speaker 1: reliable as the stars, but it's still pretty reliable, so
Speaker 1: the question would be, well, how do you detect them?
Speaker 1: One interesting fact is that the navigators Lewis learned from
Speaker 1: seemed to consult the swells based on feeling them in
Speaker 1: the body more so than looking at them, which means
Speaker 1: that they can be used to steer not only in
Speaker 1: the daytime, but on overcast nights. So when the stars
Speaker 1: are completely hidden, that's your main orientation tool gone and
Speaker 1: there's no light to see, you could still potentially feel
Speaker 1: the directional swells and get an orientation based on that. Wow.
Speaker 1: If that's interesting and it makes perfect sense. So how
Speaker 1: do you feel swells? Well, there's a part in Lewis's
Speaker 1: book where he talks about this. He says, quote Tek
Speaker 1: told me he would sometimes retire to the hut on
Speaker 1: his canoes out rigger platform, where you could lie down
Speaker 1: and without distraction, more readily direct the helmsman onto the
Speaker 1: proper course by analyzing the roll and pitch of the
Speaker 1: vessel as it cork screwed over the waves. In distinguishing swells,
Speaker 1: he stressed, you have to wait patiently until the one
Speaker 1: you want has a spell of being prominent and discernible.
Speaker 1: So there is a lot of noise in the waves, right,
Speaker 1: So there's a lot of conflicting, you know, wave wave
Speaker 1: action coming in different directions, but there's a certain pattern
Speaker 1: you can recognize from a known swell, And once there's
Speaker 1: a there's the right kind of timing in the wave
Speaker 1: action for you to identify the pattern of that known
Speaker 1: directional swell. You can orient based on that. And this
Speaker 1: would be again done by feeling it in the body
Speaker 1: and feeling the direction of the rolling of the boat.
Speaker 1: So when you think about how a boat moves in
Speaker 1: the waves, it can pitch, it can move up and down,
Speaker 1: forward to back, and it can roll from side to side,
Speaker 1: and the interaction of pitch and roll will tell you
Speaker 1: something about the direction that the swell is coming from.
Speaker 1: Right now, in saying that this type of navigation method
Speaker 1: is more reliable than it sounds, I also don't want
Speaker 1: to overstate or understate the difficulty of detecting it right
Speaker 1: that there there is a lot of noisy wave of
Speaker 1: action going on in the ocean, so somebody has to
Speaker 1: be really experienced and know what it is they're feeling
Speaker 1: for in order to feel it. And I just want
Speaker 1: to read one section of Lewis talking about attempting to
Speaker 1: understand what's going on with the navigation based on swells.
Speaker 1: Uh he writes, quote the course toward Tomaco was east northeast,
Speaker 1: directly into the cea swell that came from the same
Speaker 1: direction that it was only present or at any rate
Speaker 1: detectable occasionally at such times it could be picked out
Speaker 1: by I, and as the ship rode up and over it,
Speaker 1: meaning pitched without any role at all, except when the
Speaker 1: steep northerly wind wave happened to coincide when the boat
Speaker 1: the SPOR was rolled to starboard at the same moment
Speaker 1: as she was pitching over the head on C swell.
Speaker 1: In those long intervals where the C swell was absent,
Speaker 1: the wind wave rolled us to starboard about once every
Speaker 1: five seconds without there being any pitching component. I could
Speaker 1: feel little effect from the southeast or northwest swells. After nightfall,
Speaker 1: we steered by the stars, the swells remaining unchanged except
Speaker 1: that the wind wave declined. So that's about like trying
Speaker 1: to understand that they're different. In fact, there are multiple
Speaker 1: swells at any given time, probably hitting you from different directions,
Speaker 1: and so the experience navigator is looking for a particular
Speaker 1: type of swell. You know that you could actually make
Speaker 1: the same journey potentially and look for different swells to
Speaker 1: steer you in aid of it. You just have to
Speaker 1: know which ones you're feeling for. And that goes back
Speaker 1: to the example you mentioned earlier about just like like
Speaker 1: setting there or laying there on the boat and just
Speaker 1: waiting to to feel the one you're looking for. It's
Speaker 1: not just Okay, the waves are hitting me, I got
Speaker 1: the pattern. No, you're looking for the specific pattern amid
Speaker 1: the noise or amid the waves right when there may
Speaker 1: be multiple patterns coming at you at the same time.
Speaker 1: You're just trying to pick the right one out, get
Speaker 1: the timing right to understand, yes, this is it. But
Speaker 1: as you were talking about earlier, I think it's important
Speaker 1: to remember and again we'll we'll get more into this
Speaker 1: in the next episode. The ability to detect and measure
Speaker 1: swells and their direction of origin is not useful just
Speaker 1: in steering on the open ocean, but it's also one
Speaker 1: of the techniques for understanding wind land is near. Now,
Speaker 1: there are a couple of other things that are really
Speaker 1: interesting about navigating on the open ocean. There's one more
Speaker 1: orientation technique that is even less reliable than the others,
Speaker 1: but it is sometimes still used as a backup. That's
Speaker 1: known as the wind compass, So it's it's basically operating
Speaker 1: on the presence of known wind patterns to give you
Speaker 1: indications about about directionality. So you might, for example, use
Speaker 1: the aid of a tool here in external tool like
Speaker 1: a pennant, the you know, kind of flag object that
Speaker 1: would allow you to determine patterns of winds and where
Speaker 1: they come from. And if you know that there are
Speaker 1: certain dominant patterns of winds, you can kind of use
Speaker 1: that to give you another data point in orienting your
Speaker 1: boat in the right direction. Now there's a whole other
Speaker 1: world of ad hoc adjustment that needs to take place
Speaker 1: on top of everything we've already been talking about. You know,
Speaker 1: basically everything we've been talking about is getting the correct bearing,
Speaker 1: knowing you're going in the right direction towards your target
Speaker 1: island based on your starting point. But of course, in sailing,
Speaker 1: you can't always just sail in a straight line. Right
Speaker 1: Winds and ocean currents will gradually shift you off course,
Speaker 1: and you have to understand how that's happening and compensate
Speaker 1: for it, which again this is one of those things
Speaker 1: where I just like react to that thinking like it
Speaker 1: seems impossible, how could you do it? But but they
Speaker 1: have methods that they can do it. And there are
Speaker 1: a lot of methods here at For example, one that
Speaker 1: I really liked. Lewis discusses on the first stage of
Speaker 1: one journey with hip Hoor, departing from pula wat hip
Speaker 1: or would keep track of back bearings on the island
Speaker 1: that they were leaving to see how the current was
Speaker 1: affecting their heading. So you have the reference point of
Speaker 1: the island, landmarks the island you're leaving, and then you
Speaker 1: can see from your heading as you're leaving the island
Speaker 1: how strong the current is at the moment. And then,
Speaker 1: to to read from Louis here quote if said hip
Speaker 1: Hoor it turned out, on further observation to be weak,
Speaker 1: we would head towards the point where vegas set, which
Speaker 1: is about at three hundred and nine degrees. If strong,
Speaker 1: as proved to be the case, towards the setting point
Speaker 1: of the plea d s at about two hundred and
Speaker 1: eighty five degrees. Thus there were at least two distinct
Speaker 1: star courses traditionally laid down for this passage, and probably
Speaker 1: four to allow for strong and weak south flowing currents.
Speaker 1: This was a north flowing aren't So not only do
Speaker 1: you need to know the right headings for for the
Speaker 1: island you need to get to under you know, basically
Speaker 1: like neutral conditions, you also have to know what headings
Speaker 1: you would use if the current is a certain strength
Speaker 1: in a certain direction and the corresponding guide stars. Of course, um,
Speaker 1: but so if the wind or current is moving you
Speaker 1: laterally off course while steering in the open ocean, and
Speaker 1: so you don't have like, you know, back bearings like
Speaker 1: an island to refer to, how would you even know it?
Speaker 1: How do you know how far off course you're getting
Speaker 1: blown by the wind. This was another moment where the
Speaker 1: technique was revealed and I was like, oh, of course,
Speaker 1: I thought this method was ingenious. Some of the navigators
Speaker 1: here would look at the wake left behind by the boat.
Speaker 1: So if if leeway I mean you know, wind, the
Speaker 1: blowing the boat sideways in addition to forward, if leeway
Speaker 1: is affecting your course, one way to judge this is
Speaker 1: by looking at the degree of the angle between the
Speaker 1: straight line you're attempting to steer on. So you can
Speaker 1: imagine a straight line going from the stern to the
Speaker 1: bow of the boat, you know, and just going off
Speaker 1: towards the horizon in every direction. Look at the angle
Speaker 1: between that line and the trail of wake left behind you.
Speaker 1: This might be kind of hard to visualize without a
Speaker 1: without a picture, so I'm sorry, but Rob, I've got
Speaker 1: a picture for you to look at. Here you can
Speaker 1: see that there's actually an angle of difference in between
Speaker 1: the wake behind the boat as you're getting blown off
Speaker 1: course and the straight line that you are attempting to
Speaker 1: steer on. Yeah, you can imagine it is looking back
Speaker 1: and saying, not a straight wake behind you, going back
Speaker 1: to you know, to just directly behind you, as if
Speaker 1: it is a line drawn from the rear of the vessel,
Speaker 1: but something that is diagonal because because of the way
Speaker 1: the wind is blowing the vessel from the side right.
Speaker 1: So by seeing that angle and how large it is,
Speaker 1: a master navigator is able to correct for the amount
Speaker 1: of leeway that they're being blown off course. Thank thank you. Now,
Speaker 1: there's a huge thing that we haven't gotten into in
Speaker 1: detail yet here, but a big section of Lewis's book
Speaker 1: is about the Pacific navigation forms of dead reckoning and
Speaker 1: dead reckoning is estimating the position of your boat without
Speaker 1: reference to any new markers around you, but rather by
Speaker 1: knowing your past position and estimating how far you have
Speaker 1: traveled from there and in what direction. So this is
Speaker 1: crucial to keeping track of your journey. But this is
Speaker 1: a different thing because it's not giving you new information
Speaker 1: from your surroundings. It's rather a sort of keeping track
Speaker 1: of your position on a mental map by just using
Speaker 1: the information already in your possession. And one mental tool
Speaker 1: that seems to help with this process and Pacific navigation
Speaker 1: has been referred to as attack. Again, this is not
Speaker 1: a means of acquire ring new information from the environment,
Speaker 1: but rather a visualization or a mental reference system for
Speaker 1: understanding one's place in relation to other things. Unfortunately, this
Speaker 1: is yet another concept that is kind of hard to
Speaker 1: explain without visual aids. But Rob, I've got a visual
Speaker 1: aid for you to look at here, and I will
Speaker 1: do my best to try to explain it. Basically, it
Speaker 1: hinges on having this mastery of relationships between stars, vantage points,
Speaker 1: and various geographical locations, specifically islands on in the nearby surroundings.
Speaker 1: So it's a point of analogy imagine that you want
Speaker 1: to travel between New York and Chicago by stars. One
Speaker 1: way that I can help understand where I am along
Speaker 1: my journey is if I have a third reference point
Speaker 1: in mind. So let's say Atlanta. So I know that
Speaker 1: I start in New York, and when I start in
Speaker 1: New York, I know from where I am, Atlanta is
Speaker 1: going to be under Star A. From my point of views.
Speaker 1: If I wanted to travel to Atlanta, I would take
Speaker 1: my beer, I would head towards Star A on the horizon.
Speaker 1: But by the time I reached Chicago, now, because I'm
Speaker 1: at a different vantage point, Atlanta is underneath Star C
Speaker 1: from my point of view. And there's a midpoint in
Speaker 1: between Chicago and New York where Atlanta from my vantage
Speaker 1: point is underneath Star B. So the whole time I
Speaker 1: never see Atlanta. But this mental reference system allows me
Speaker 1: to break my journey into recognizable segments where I keep
Speaker 1: track of each time the third reference island or in
Speaker 1: my analogy, Atlanta has moved under a new star from
Speaker 1: my point of view. Does that make sense? Yeah, I
Speaker 1: think so. And this this visual reference helps a bed. Yeah,
Speaker 1: I'm sorry you folks at home can't see it. But uh, actually,
Speaker 1: you know, if you do, if you do just a
Speaker 1: Google search for ETACH reference points, I don't think you
Speaker 1: will find the exact um illustration that I'm looking at,
Speaker 1: but you'll see some that are similar to They give
Speaker 1: you an idea of what we're talking about. It's e
Speaker 1: T a K. Though it's complicated by the fact that
Speaker 1: this appears also to be the name of a like
Speaker 1: a car navigation system uh software. So if you if
Speaker 1: you google atak islands there you'll see the right illustrations. Yeah. Yeah,
Speaker 1: that'll cut out some of the car stuff. But I
Speaker 1: think this system is is also really interesting because it
Speaker 1: I think it still is important to think of it
Speaker 1: as a useful tool for navigation, even though it provides
Speaker 1: no additional information to the navigator. Instead, what it is
Speaker 1: is it seems to be that it's useful as a
Speaker 1: system for mentally keeping track of the information you already have,
Speaker 1: for knowing how far you've come, where you are, and
Speaker 1: how far you have left to go. Uh, which is
Speaker 1: interesting because I mean, obviously that's an important part of
Speaker 1: of any travel, right is sort of vision ualizing the
Speaker 1: whole of your journey in ways they're not immediately apparent
Speaker 1: to your senses. Yeah, and I guess as in modern
Speaker 1: travelers with modern instruments, be it at sea or on land. Yeah,
Speaker 1: we're still engaging in some level of that. We still
Speaker 1: have some level of a mental map, but we have
Speaker 1: these other tools that make our mental map less important.
Speaker 1: Maybe sometimes the mental map is even incorrect. Like you know,
Speaker 1: if you're if you're lying heavily on a GPS device
Speaker 1: to drive you from one point to the other. I
Speaker 1: guess you could theoretically not know if you're really driving
Speaker 1: north or west or south or what have you, as
Speaker 1: long as the system got you there. But in this case,
Speaker 1: the mental map is everything. The Milton in the mental
Speaker 1: map has to be carefully cultivated using uh knowledge of
Speaker 1: all of these environmental cues, these different systems. Uh, it's
Speaker 1: it's really quite quite amazing. Uh it's uh yeah, it's
Speaker 1: it's it's something else. So when you're driving somewhere knew
Speaker 1: that you've never been before with the aid of a GPS,
Speaker 1: you know, like a map, SAP on a phone or something,
Speaker 1: can can you just plug it in and go or
Speaker 1: do you, like me strongly prefer to look at the
Speaker 1: whole route first. Um, I tend to just go the
Speaker 1: same way I do recipes for meals. It's just I
Speaker 1: just trust that. I mean, I look and to make
Speaker 1: sure I have what I need. In the same case,
Speaker 1: I'll look at my gas tank and make sure have
Speaker 1: enough gas to get where I'm going. I'll see how
Speaker 1: much how long it says it's gonna take for me
Speaker 1: to get there, But then I'll just go. I'll just
Speaker 1: start cooking, or I'll or I'll just start driving and
Speaker 1: trust that I will get there and I'll figure out
Speaker 1: on the way of there any snacks. This must be
Speaker 1: differences in personality types somehow, I guess I'm I'm more
Speaker 1: annoying about this or something. I really don't like having
Speaker 1: to navigate based on just a moment to moment directions
Speaker 1: on an app without seeing the entire route first. I
Speaker 1: like to look at the whole map, see what the
Speaker 1: steps are, see how far it is, see like, see
Speaker 1: it visually represented. That really matters to me for some reason.
Speaker 1: I mean, I might glance at it if if I
Speaker 1: know there's going to be some weird exit, if it
Speaker 1: says that, oh, I'm getting off at this exit, and
Speaker 1: normally I don't do that. I'm kind of curious what
Speaker 1: route I'm taking then, but otherwise I just go, well,
Speaker 1: you know. The weird thing is, I think one reason
Speaker 1: I do that, it's not like it usually gives me
Speaker 1: important information that I actually need in addition to whatever
Speaker 1: the step by step instructions in real time are. Instead,
Speaker 1: I feel like it's something closer to the attack system,
Speaker 1: where I just want to be able to visualize in
Speaker 1: this abstract way the whole of the journey and sort
Speaker 1: of imagine where I am along the journey at various points.
Speaker 1: M yeah, but I feel like I'm going to do
Speaker 1: that anyway as I drive, Like there's kind of a
Speaker 1: perhaps a less accurate version of that that's going to
Speaker 1: be going on in my head, but it says it's
Speaker 1: as accurate as it needs to be. Like if the
Speaker 1: GPS satellite sort suddenly get taken out by aliens or something, um,
Speaker 1: you know, I could I get backtrack, or even if
Speaker 1: it's if I've driven this particular route before, I can
Speaker 1: probably remember the rest of the way. Um. But otherwise
Speaker 1: I'm good. Well, I wonder if we should call Part
Speaker 1: two there and then come back in part three to
Speaker 1: talk about one of the next really interesting things which
Speaker 1: is all of this has been mostly about navigation, direction
Speaker 1: finding and navigation, especially on the open sea, but a
Speaker 1: whole other part of this science of navigation is land finding.
Speaker 1: When you're getting close to an island, how do you
Speaker 1: know that? And how do you find it? And so
Speaker 1: let's save that for part three. Yeah, part three, we
Speaker 1: will we will make landfall or try to make landfall appropriately,
Speaker 1: all right. In the meantime, if you would like to
Speaker 1: check out other episodes of Stuff to Blow your Mind,
Speaker 1: you know where you can find them in the Stuff
Speaker 1: to Blow your Mind podcast feed. We have core episodes
Speaker 1: of Stuff to Blow Your Mind on Tuesdays and Thursdays.
Speaker 1: On Monday's we do a little listener mail. On Wednesdays
Speaker 1: we do short form episode we're calling it The Art Fact.
Speaker 1: And then on Friday's we do Weird How Cinema. That's
Speaker 1: our time to set aside most of the science and
Speaker 1: the culture and just talk about a weird emotion picture
Speaker 1: and we have reruns on the weekend. Huge thanks as
Speaker 1: always to our excellent audio producer Seth Nicholas Johnson. If
Speaker 1: you would like to get in touch with us with
Speaker 1: feedback on this episode or any other to suggest a
Speaker 1: topic for the future, or just to say hello. You
Speaker 1: can email us at contact at stuff to Blow your
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