From the Vault: Pacific Navigation, Part 3

The original discoverers of the Polynesian Islands traversed a vast ocean, bringing civilization to islands untouched by human activity. How did they do it? In this classic Stuff to Blow Your Mind two-parter, Robert and Joe discuss the sheer scale of the Pacific Ocean and environmental navigation. (originally published 7/13/2021)

See omnystudio.com/listener for privacy information.

Episode Transcript

Speaker 1 (00:05):
Hey, welcome to Stuff to Blow Your Mind. This is
Robert Lamb and I'm Joe McCormick, and it's Saturday. Time
to go into the vault. This is part three of
the series we've been running. This week. There are episodes
on Pacific island navigation. This episode originally aired on July.
I remember the series very fondly, so we hope you

(00:25):
enjoy it. Welcome to stot to Blow Your Mind, production
of My Heart Radio. Hey, welcome to Stuff to Blow
Your Mind. My name is Robert Lamb and I'm Joe McCormick,
and we're back with part three of our series about

(00:46):
ancient Pacific Island navigation. In the previous couple of episodes,
of course, if you haven't listened to those, you should
go back and check those out first so you can
understand what we're talking about today. But in the last
couple of episodes, we talked about a lot of these
fascinating mysteries about the population of the Pacific Islands and
and how those islands were first colonized by humans, how

(01:06):
people found them, and then how people traveled between them
once they knew where all the islands were. Because, of course,
this is a huge area of the surface of the
Earth that is covered almost entirely by water and only
polka dotted with these tiny islands here and there. And
yet somehow, without charts, without instruments like a like a
compass um, the navigators of the Pacific Islands were able

(01:29):
to reach the other islands in in the surrounding areas
with this amazing level of accuracy. So in the first
episode we talked about some of the history theories about
the history of the settlement of these islands, and then
in the last episode we talked about techniques that have
been documented that allowed master navigators to locate and and

(01:49):
sail to islands in this in this vast ocean with
enough accuracy that they could do so reliably over and
over again. And what those techniques without charts and modern
instruments would have been. Yeah, this this whole realm of
environmental navigation, which I just want to drive home again
when we're talking about this, we're talking not about some

(02:09):
sort of innate art or something that is just uh,
this one acquires by you know, being out in the
water or being uh, you know, growing up on the ocean,
that sort of thing. Now, this was this was a
science that was learned that was passed down from generation
to generation across these these different Pacific cultures. That's right.

(02:30):
One of the main sources we've been referring to is
a very important book in the history of of studying
these techniques that was by a scholar named David Lewis,
and it was published with the University of Hawaii Press
in nineteen seventy two. It's called We the Navigators, The
Ancient Art of Land Finding in the Pacific. And one
thing that's really really cool about this book is that
Lewis sailed well. He he interviewed many master navigators of

(02:55):
different Pacific islands in Micronesia and Polynesia, but he also
sailed with several navigators including UH, two very prominent navigators
named Hippur and Tevik, from whom he learned a whole
lot about these these techniques firsthand at sea, like they
were navigating his boat, which was a boat called the
Ispiorn and UH, and so we got to see these

(03:16):
techniques firsthand. And so in the last episode we talked
mostly about techniques for navigation on the open sea. Direction finding,
so especially using the stars to to orient towards your targets.
And UH, and then using backup methods as well, such
as like using the sun during the daytime and navigating
by directionally reliable c swells, which was especially astounding to me,

(03:41):
like the idea that you know, you could learn how
to feel for certain patterns of c swells that reliably
come from a certain direction and then use that to
know which way you're heading. Um. And then also, of
course you would have to pair these direction finding techniques
on the open sea with the system of dead reckoning,
which is noing how far you have traveled based on

(04:02):
your rate of travel, your starting position, and your direction
of travel and sort. And so that would be a
way of sort of record keeping your journey mentally as
you're going along the way, even though you don't necessarily
have new environmental clues to choose from. But today we
wanted to get mainly into the question of land finding.
So a traditional Pacific navigator has used open sea navigation

(04:26):
techniques like celestial orientation and dead reckoning to get roughly
to the vicinity of an island. Once you are nearing
your destination, how do you actually find the land? Yeah,
because we discussed in the previous episode, you don't want
to you know, be sailing in the right direction to
be in the vicinity of the island, and then not
be able to see it too again again, not be

(04:48):
close enough to pick up on the very obvious cues
that you were near the island, and have to pick
up on those more subtle cues that would require training
and expertise to notice. Right, I mean, one of the
biggest dangerous actually for a Pacific Island sailor is missing
your target, is going past the island you're trying to
get to without realizing it. Yeah, I mean, in a

(05:11):
very very loose sense. It's like depending on say, your
your GPS navigational system, which we refer to previously, you know,
using that to get to the immediate area, like the
block where the where the store is that you're trying
to go a store you've never been to before. But
then once you're there, the GPS is only gonna help

(05:32):
you so much. Then you're gonna have to pinpoint the sign,
figure out which storefront it is, figure out your parking, etcetera.
There are a whole new set of problems that your
mirror navigational system, your GPS, is not able to help
you with. Right, and so one thing that's very interesting
that David Lewis explores in his book is what he
calls the idea of expanded target landfall. And what that

(05:57):
means is that by using a swim wheat of land
finding techniques, you can essentially extend the radius of land
a certain reliable distance out into the ocean. And I'll
talk about the distances as we go on, but there's
a certain reliable distance out into the ocean that you
can just expect to be able to detect nearby land,

(06:19):
even if you can't see it. And if you measure
land including those radii out into the ocean beyond the
shore and uh and especially beyond sort of like reefs
and submerged or or almost submerged a toolls nearby, you
can actually greatly expand the percent of the Pacific Ocean

(06:40):
that is taken up by by by land range. Basically,
so you can expand your target from these tiny islands
surrounded mostly by water to basically a block of islands
with mostly or totally overlapping ranges of land detectable water.
Does that make sense, yes, Yeah, basically increases the the

(07:05):
the footprint of the island, like the the detectable footprint
of the island right. So, so, of course the direction
finding techniques like celestial navigation are extremely important in getting
you towards your your target, but also the expanded target
landfall is just as important, if not more important. I mean,
I guess you can't really have one without the other.

(07:25):
It is also extremely important because you know, there's only
so accurate you can get with steering by stars. You
still need to be able to correct course and find
the land once you're close enough. And so, how far
exactly can you expect to find land from out in
the ocean. Well, it does very a lot, depending on
local conditions. But Lewis cites a scholar named Frankel who

(07:49):
estimates that on average, land can usually be detected from
about thirty miles in any direction, and Louis essentially agrees
with this number. Uh, And then he writes the US quote,
if we draw circles with thirty miles RADII around each
Pacific island, we find that the circles overlap over vast areas,
giving rise to solid blocks i e. Islands separated by

(08:13):
not more than sixty miles passing between which a canoe
could not be more than thirty miles offshore. So with
these expanded target landfall techniques, the problem of finding these
tiny islands in the vast ocean actually is much more manageable.
It's reducible more to finding these blocks or screens of

(08:35):
islands within a certain angle, you know, a certain angle
of direction from your starting position. So it means that
what would otherwise be a sprinkle of islands becomes a
clump of islands, yes, which there's some there. You actually
shared a wonderful map here that that that demonstrates this,
and it's really it's really quite impressive, okay, because you

(08:55):
can see it making a huge amount of difference, uh,
is you're traveling, you know, between these these islands, uh,
potentially even charting some of these these more distant journeys.
That's right. So if you're looking at it from a
map that includes expanded target landfall, is sort of a
black circle around the island. What would have been a
smattering of of little tiny dots instead turns into a

(09:18):
big clump of black circles that they're all overlapping each other.
So this really does help with the problem. But of
course you could easily once again pass between these islands
without actually being able to see them visually. So you
need to be able to know what to look for.
And again one of the things that stressed, especially in
we the navigators, is that the degree of what they

(09:42):
call screening the screening of islands rather than individual island targets.
So you would aim for a screen like a line
of islands that are all overlapping within land finding range
of one another. That the the degree of screening of
an island or island group target was the number one
safety concern when making a journey there, So more screening

(10:05):
more overlapping of the expanded targets is safer, and less
screening where there are gaps between the expanded targets is
much more dangerous because again of the danger of unknowingly
passing your target. But I guess we should talk about
what are the actual landfall signs? What are the environmental
signs that can be used to detect a land from

(10:26):
a long distance away. I guess we should start with
the one that is the most obvious. Maybe this one
doesn't actually need to be said, but there are a
couple of things about it that are worth sorting out. Actually,
So the most obvious one is high ground right. In
some cases your target island is very tall and it
can be seen from very far away. So for example,
Tahiti reaches elevations of something like seventy feet, and for

(10:49):
this reason, the land itself can sometimes be seen from
as far as eighty miles away. That that's a real
good distance. And likewise Hawaii that can be seen from
extremely far away. It can volcanoes and rising land masks
that sometimes up up to like thirteen thousand feet. But
not every island is tall like this. Many Pacific islands

(11:09):
lie more or less at sea level, with nothing much
taller than the height of a palm tree, and you
can easily miss these. Standard navigational lore holds that on
these low islands, visibility is about ten miles given the
presence of coconut palms, which grow to about seventy five
ft high, so at about ten miles you should be

(11:29):
able to see the tallest of the coconut palms. It's
interesting I was reading about about this and it reminded
me of our episode on on the font of Morgana,
where we talked about mirages and about how in some
cases there were islands that we even put on maps
that turned out to not be real. They were based
on on mirrages, and the reverse of that is also true.

(11:51):
There are islands that um certainly as as European powers
were coming into play and trying to map everything out,
there were islands that were that were known to be
to exist by by the natives, but various Europeans would
would have would decide why this was probably a mirage.
We don't have yet, we don't know exactly where it is,

(12:12):
but it would turn out it was actually there. Yeah,
and it's funny you should bring up the fed Amorghana
episode because this land finding technique is way down the
list in terms of of how commonly it was used
in the level of priority it's given. But one of
the things mentioned in this book is that land loom
the optical illusion of being able to see the land

(12:34):
in a in a superior mirage projected up above the horizon,
even though the land is not visible itself from where
you are. This actually was sometimes used by some Pacific
Island navigators, specifically Lewis Sites navigators from the Gilbert's using
this one. But coming back to the idea of vantage
points and high ground, there is actually a pretty reliable

(12:57):
mathematical equation you can use for determining the visibility of
an object over the horizon at sea. Uh and and
it goes like this, So you take the square root
of the height of the object you're looking for in
feet and and so this is this method will be
unit dependent. But the square root of the height of
the object in feet. So that could be a you know,

(13:18):
a seventy five ft tall palm tree, or it could
be a mountaintop or a lighthouse, whatever that is. And
then you add that to the square root of the
observer's height, so that would also be in feet. If
you're you know, if your eyes are five feet above
the water, that's five feet, or if you're sitting down
in a low canoe, it's probably even lower. And then
you you add those together and then you multiply by

(13:41):
I've seen different numbers. Actually I found a navigational website
that suggested multiplying that number by one point one seven.
Lewis gives gives the idea to multiply by one point
one five. But whichever way you do, you'll probably get
pretty close to the same answer. And this will give
you the distance away in miles that an object can

(14:02):
usually be seen over the horizon. But that made me
think about the height of the observer, which makes me
wonder about the land finding virtues of different watercraft, right,
because they're obviously different kinds of watercraft. People make these
journeys and sometimes there and they could be an outrigger canoes,
or they could be in a double hulled traditional navigational

(14:24):
vessel that would have a much more raised platform in
the middle with even a cabin that I guess you
could technically get on top of. I don't know how.
I don't know what all of the techniques with with
ancient Pacific watercraft would be for getting higher up as
a vantage point, but that seems like that that could
give you an advantage as well, right, because of course
they would not have the advantage that that you would

(14:45):
have with again a crow's nest lookout in a western
sailing vessel, like you know, a large scale ocean voyaging ship.
That's right, but uh, fortunately, these these specific navigators had
lots of other environmental cues they could look for. And
these cues are very important because even with taller islands,

(15:06):
so even if you're trying to get you know, to
a place that's mountain. As you're trying to get to
Tahiti or Hawaii or something, environmental conditions can render these
less visible. So Louis gives the example of mountains the
mountains of Mangareva and Truck, which should be visible based
on their height from like forty five miles away, but
he says that in his case, when he was once

(15:29):
approaching in in the boat, they were unable to see
the peaks of these islands because of overcast, and so
their first visual sighting was actually of the surrounding barrier
reef rather than of the island itself. Now, as we
go on to discuss more of these land finding techniques,
it's important to note that they vary in both directions,
meaning that the land finding techniques very in preference of

(15:52):
individual navigators and navigator cultures and in availability at target.
So there are some like, uh, there some traditions of
land finding lore that place more emphasis on one or
the other. But also you need to have the backup
knowledge because you're not always going to be able to
find all of these when you look for them. Yeah, again,

(16:12):
this is a suite of tools that one that a
navigator would use. This is a toolbox of different techniques,
and you're not gonna want to depend on just one
of them. Now you're gonna use several of them, and
some of them are gonna better than others. But when
used in congress, UH, you can get the train navigator
can get really positive results. Now there's one thing that
Lewis mentions in this book which I thought was interesting,

(16:33):
which is a sort of counter example to uh, the
thing we've talked about a couple a couple of times,
which is that he says, you know, none of the
navigators he spoke to or traveled with ever ever appealed
to the idea of a sixth sense. Right, you were
mentioning this earlier. It's not just intuition about being at sea.
When they were making navigational decisions, they could always point

(16:54):
to specific markers. They could say the reason I'm going
this way is because of this. It's something that was
in the environment that could be pointed out and understood.
So it wasn't just a gut feeling. But one place
in which he does say intuition seemed to come in
was in the calculus of how much to wait different
types of observations of land finding signs so navigators might

(17:18):
get close to an island and you'd see one kind
of sign and then another one, and they'd be trying
to decide which way to go based on maybe different
conflicting signals, or or what what the sort of sum
total or average of the evidence was. And that did
seem to be more based on a gut feeling after
surveying all the evidence available to them. So I thought

(17:39):
that was an interesting counterpoint. Thank thank thank so. The
first big sign to mension, I think would be birds. Uh.
There's actually a part where where Lewis cites a navigator
named Tita who says that who is quoted at length

(18:00):
on this He says birds are the navigator's very best friends.
Birds are useful up to twice the site range of
an island from a canoe. And he also says the
site range of land is about ten miles and that
of birds twenty. The birds which are the most significant
are turns and naughties. Yeah, I've read that. You know,
a lot of it comes down to familiarity with bird species.

(18:22):
It's not just of course birds in general, but specific
knowledge of how far out to see a particular bird
species will typically go. So if it's a If it's
a sea bird, for instance, the distance could be somewhere
in the neighborhood of a hundred kilometers, which is about
sixty two point one miles um. You know, again, it's

(18:43):
just going to depend on the exact variety of bird uh,
while other varieties of birds are going to stay much
closer to land. That's right. So yeah, you need to
look not just for birds in general, but for specific
species of birds, because there are, as you mentioned, pelagic
species like petrolls and sheer waters that will just not

(19:03):
lead you to land with any reliability. If you follow them,
you may end up cruising out into the deep and
not coming back. But once you get within about thirty
to fifty miles of shore, you will start to see
some familiar species that are somewhat reliable. So first of all,
you'll see booby birds uh and sometimes predatory frigate birds.

(19:24):
At this distance of thirty to fifty miles, and then
even closer, within about twenty to twenty five miles of
the nearest atoll, you will get what what Louis says
are quote mixed flocks of white turns and naddies that
will be encountered busily searching for fish, and once again
they show no more interest in directing the wayfarer than

(19:44):
a busy New York policeman. Uh So, so there's some
further deduction you have to do. It's not just like
you see the birds and then you immediately know what's up.
If you see booby birds, frigate birds, turns and naughties,
you know you're close. But you can't really use their
flight paths and behavior throughout the daytime to know which
direction land lies. So what do you do? We have

(20:06):
to use time of day. These species roost on land
and they have to return to solid ground daily, and
so the time of day tells you a lot. They
typically fly out to their fishing shoals from land in
the early morning, and then they return to land in
the evening. So to read a passage from from Lewis
here he writes quote towards evening, the frigate birds, for example,

(20:28):
will be seen to abandon their leisurely patrolling, climb even higher,
and set off in one direction, probably homing by sight.
About the same time, the boobies will tire of their
inquisitive inspections and fly low and arrows straight for the horizon.
As the noddies depart, they will weave slightly in and
out between the crests of larger waves, while the turns

(20:50):
will be flying a little above them, but all will
be following a very exact path towards their home island.
So once you are within range of land, and you've
gotten there again by the process of of of open
sea navigation, often by the stars and uh and then
these backup methods together with dead reckoning, you get within
range of the island, you start to see certain bird

(21:10):
species and you know which species to look for and
what time of day to follow them. And if you
see the birds all trending in the same direction around sundown,
then you know. There are also a few stories here
and there about islands where some sea going birds have
been domesticated, you know, like fed and trained. But these
stories seemed kind of vague and uncertain, but it is

(21:32):
at least an interesting possibility to consider whether there's much
to it or not. Like, what if an island culture
could essentially train frigate birds to be the walmart graters
of the island. Yeah, yeah, and almost like living lighthouses
in some respects. Yeah, because the behavior of birds can
factor and apart from just uh you know, flying back

(21:53):
like booby, birds are considered useful in that they will
not only fly towards land at the close of day,
they will often take an active interest in approaching boats
and they will try to land on them, like land
on the rigging or something, before eventually flying off towards
home in the evening. Now, I know a lot of
you out there probably watched The Simpsons or watched The
Simpsons in the past, and you're probably thinking about the

(22:14):
scene in the episode Boy Scouts in the Hood. Uh uh,
this is the the episode and well, let's see, I'm
trying to remember exactly how it went. Did they get
lost at sea? Well, first they get lost at river,
which then results in them being lost at sea, and
they're trying to get back to land and then what
do they see in the sky? They see a seagull.

(22:34):
Is this the one that starts with Bart wanting a
knife but to get the knife? Yeah, and he has
to read the book don't do what Donny Don't does.
But yeah, it ends up with them doing a boy
Scout river race and so they're lost at sea and
what I don't remember what happens with the seagull. I
think Ned declare Ned is with them, and Ned looks
up and he sees that there's a seagull, and he

(22:55):
declares that they're saved. Um. But then it is it
is it is brought up that seagulls only go out
to sea to die, and then the seagull die, so
they're still lost. Uh. Now, I was thinking about this
in connection with with with some of these islands, particularly
with the Hawaiian Islands. And this is a fun fun
fact of the various species of seagulls out there, and

(23:17):
there are many. Seagulls are not one species, they're multiple.
You'll find some of them in the Hawaiian Islands. But
a great mini goals cannot survive in Hawaii because the
islands lack the sort of shallow coastal scavenging waters that
one finds in continental settings. Some of these goals do
wind up in Hawaii, but only to starve to death

(23:38):
because they do not have the environment and they need
to survive. Well. That actually ties into the next thing
I wanted to mention, which is that everything we've talked
about so far is in the context of land finding
by way of local birds in a near radius to
an island, you know they live on the island, and
once you see them, you know you're near the island.
You can follow them home. But there's another use of

(24:00):
bird navigation entirely, which is the possibility that some ancient
Pacific islanders deduced the presence of previously unknown islands by
observing the migratory patterns of land birds. Stories like this
exist in some island sailor lore, So it seems quite
reasonable to assume that that some islands were indeed discovered

(24:21):
this way. But ultimately it's it's historical speculation and we
don't know for sure, but that that does seem like
a very plausible guess as to how some of these
islands were found when they had never been seen by
humans before. I should also add that, above the various
birds you could site that would give you an indication
that you were near land, the dodo the absolute best.

(24:42):
Once you've once you've spotted the dodo, you're good to go.
But by the way, if you find yourself in Hawaii,
if you find yourself on the island of Oahu, I
highly recommend going to the Bishop Museum there. Um it
is it is a wonderful museum that covers so much
about Alnesian culture and uh in Hawaiian history, and it

(25:03):
covers some of what we're talking about here there there
there's stuff about the canoes that were used, the navigational
techniques that were used, and and so forth. So I'm
sure the Bishop Museum will come up again, but I
highly recommend it that you if you, if you visit
the islands, you you kind of owe it to yourself
to go to the Bishop Museum. All right, so we've

(25:24):
talked about high ground, we've talked about birds. What's next. Okay?
The next one is is fascinating to me and and
it is the use of clouds to find nearby land.
So you might think, well, how could you use that?
I mean, there are clouds over the open ocean. What
what would clouds tell you? But it turns out they
can tell you quite a lot. There. There is this

(25:46):
tradition among Pacific navigators of looking for your target by
what's known as land clouds, patterns of cloud formations that
are consistent with the presence of land rather than open water.
So how would clouds appearing over an island be any
different than clouds appearing anywhere else. Well, well, they're actually

(26:07):
a number of signs that are used. So navigators claim
first of all that clouds move more quickly over open
water and more slowly over land, almost as if they
appear to become stuck over islands that are hidden beyond
the horizon. But there are also a number of difficult
to describe characteristics that these navigators look for having to

(26:28):
do with the formation, appearance, and behavior of clouds over
dry land, And one example is the the telltale shapes,
specifically the eyebrows and the V shape. Both of these
are referred to, for example, by a navigator named Aberra,
that is that was extensively interviewed by by David Lewis
in his book. And so according to the navigational lore

(26:51):
of Aberra, uh the eyebrows meaning these I mean, I
guess I can't describe them any better than that clouds
that look like eyebrows appear in the sky over where
an island would be. So if they are eyebrows, you'd
imagine the island down below the horizon is sort of
where the noses or maybe where the lips are, so
it's between the two eyebrows and these eyebrow looking clouds

(27:12):
are more common when the weather is calm and there
are no other clouds, whereas a different formation known as
the V shape, the V shaped column is present over
islands when there is wind and when there are other clouds,
and the V shape basically the vertex of it at
the bottom points down to where the island is. But

(27:32):
even more fascinating than that to me is that experience
navigators mentioned that there are cues rooted in the color
of clouds. Clouds hovering over an island below the horizon,
we will tend to have different colors and levels of
brightness than clouds floating over the ocean, And apparently a
lot of this has to do with the actual reflection

(27:54):
of the colors of the land lying below the cloud.
It's amazing. Yeah, yeah, this is really neat. I was
reading about this specifically as it concerns lagoons. Lagoons being
shallow bodies of water, uh, the open ocean being deep water,
and therefore the lagoon water as reflected in the cloud

(28:15):
will be a lighter shade of blue. Um. So yeah,
that's so, you know, it's not like a mirror. You're
not gonna be like, oh look, I can see the
reflection of the entire island to which we are going. No,
but to the trained I you would be able to
see the difference in the color, like there's a lighter
blue reflected in the clouds, that that must be the
blue of the lagoons on the island. Though I should,

(28:36):
of course also stressed this, like a lot of the
things we're discussing here, we should add the caveat under
the right conditions exactly so none of these signs we're
talking about are always observable. Uh and and Lewis stresses
this a lot, that it requires consistent, focused attention in
looking for all of the available cues that you know about.
So looking for a few minutes you are quite likely

(28:57):
to see nothing to get no cues. But if an
experience navigator pays close attention for several hours, usually at
least one type of land sign will manifest. And just
to get a sense of what the the the effects
of reflected color from land on the clouds would be, like,
I want to read a section from Lewis here where
he describes some examples. So he says, quote, the colors

(29:20):
that begin to appear closer to land very with the
makeup of the island. There are three kinds of island
with corresponding clouds. Tita says, above lagoon islands, the cloud
roof tends to be greenish. Over extensive areas of white
sand or surf, the cloud or a portion of it
will be brighter, more white than the rest. The clouds

(29:41):
above a wooded green island will be darker than their neighbors.
Abera referred to a pink tinge over reefs and green
above lagoons. Re We likewise said that lagoon islands reflect green,
and ones without lagoons a reddish color. Islands with no lagoons,
like Kuria said Yo Tibata, reflect a dark color that

(30:04):
must be distinguished from rain cloud, which appears very similar.
Islands with big stretches of dry reef or mangroves have
bright colored clouds above them. And then he mentions that
given the fact that all of the stuff he's just
been saying comes from different interviews with different navigators from
different islands, and with four separate interpreters transcribing what they

(30:26):
were saying, uh, the fact that they're so consistent in
what they say about the colors reflected in the clouds
is pretty amazing. Now there's another very important thing that
I'm not going to spend a lot of time on,
just because we discussed it somewhat in our previous episode
and now in the last episode we talked about feeling
for swells in the sea as a way of direction finding,

(30:46):
but also a navigator can feel for the reflection, refraction
and interference with swells with no notion swells to detect
that land is nearby. And Lewis goes into deep detail
on this practice in his book. But essentially it's it's
a similar to feeling to direction finding with the help
of swells, except feeling for interruptions and swells and reflections

(31:09):
of swells from known land masses. But there's one last
thing I wanted to talk about here that is really
interesting and almost kind of creepy, especially because it is
to some degree still mysterious, though there there's some ideas
about what it might be. Uh. So we've talked, you know,
at length before about bioluminescence in the ocean, you know,

(31:29):
kind of that is a regular profuse light in the
water from organisms like bioluminescent plankton and uh and Lewis
recounts in the book that some navigators say that bioluminescence
in the water just doesn't tell you much useful. Other
sources seem to think it increases when near near land
or a reef. But in any case, it's important to

(31:51):
distinguish regular bioluminescence in the water from this next land sign,
which is fascinating. And it's what David Lewis calls d phosphorescence.
But it is also known as ta lapa spelled t
E space l A p A. The navigator Tevak calls this,
calls it underwater lightning. It's also described by another navigator

(32:13):
as ulo a tahi or the glory of the seas.
And so I wanna read Lewis describing what this is.
He's just picking up after tek has has called it
underwater lightning, which he thinks is an excellent analogy, and
Lewis writes quote, it comprises streaks, flashes, and momentarily glowing
plaques of light, all well beneath the surface, exactly like lightning.

(32:37):
It flickers and darts and is in constant motion. It
occurs a good deal deeper down than common luminescence, at
anything from a foot or two to more than a fathom,
all right, So that's already strange because you know, otherwise
I'd never heard of anything like that anymore, flashes of
light from deep under the water, almost like lightning. But
it gets even weirder. Apparently, tailapa seems to flash from

(33:02):
the direction of an island or a reef. You can
see it well into the deep sea when you're eighty
two a hundred miles away from land, but as you
approach the island, the flashes of light become more and
more rare, and then they disappear entirely as you get
really close. The distance from land or from reefs also
seems to affect how the light moves. They're slow flashes

(33:24):
of light far out at sea, but then about ten
to twenty miles from land it starts to take on
a rapid, whipping back and forth movement. And uh and
it's also generally understood that tai lapa coming from reefs
is slower moving than tai lapa coming from islands. So
this was amazing to me because I had never heard
of anything like this before. Yeah, yeah, this was definitely

(33:46):
new to me as well. Um, and it is mysterious
sound and the idea of underwater bioluminescent lightning being some
sort of guide again, like all of these things, not
the primary guide, but some additional tool that you could
turn to. Right. Well, one thing I want to note
what you said, it's the tailapa is bioluminescent, which it

(34:07):
may well might be, but it might be some other
kind of luminescence as well. It's still there's still some
question about what causes it, and we'll discuss that more
in a minute. But uh, but yeah, I think it's
not a given that it's necessarily bioluminescent, like the you know,
the like the general sort of ambient glow that you
see in the upper area of the sea that's known
to be bioluminescent. But it's important that what you say

(34:30):
that this is very much a backup method and it's
not known to everyone. So Lewis documented references to it
in the navigational lore from two Polynesian areas and one
Micronesian area, but there were plenty of other navigators who
didn't seem to know anything about te Lapa, like they've
never even heard of this concept. Yeah. One of the people,

(34:51):
the more recent people that we were looking at concerning
this topic, is a Harvard physicist by the name of
John huth Um and uh, and he points out that, yeah,
and cultures you just see no mention of it, the
Marshall Islands being one that he specifically mentions where they
just didn't didn't have the concept. And and it's unknown
exactly why is it an environmental reason, like whatever this

(35:13):
phenomena is, it's not it wasn't present, uh, you know
around the Marshall Islands or islands that were of interest
to these navigators, or is it a situation where for
this particular culture they found that this was not a
reliable navigational tool and it just wasn't worth keeping around,
Like it's not one you could lean heavily on and

(35:34):
it would always be just kind of like a second
or third tier backup. Anyway, it remains a mystery. Yeah, yeah,
So some islanders explained that as this backup method of navigation,
they could use t LAPA to steer on dark, rainy nights.
So maybe you can't see the stars, you can perhaps
see these flashes of underwater lightning. And Lewis actually documents

(35:57):
that he himself observed it. That was one night when
it was late at night and it was dark and
he was sailing with Tevak. This was on the thirty
one December, he writes, quote Land Lapa was seen to
be darting to and fro along two distinct bearings, which
were both plain enough for me to see despite the
clear night and the comparative nearness of the islands. One

(36:19):
series kept flashing from a direction which tevk averred was
that of the volcano Tina Coula. The other, he said
was from the island of Nadeni. Morning revealed the high
islands of Tina Coola and Nadini, each about twenty miles
away and respectively west and south of our position. These
were the directions that the old navigator had indicated. So

(36:42):
in this experience, he says, yep I saw it. Tek
told me it was there. I looked and I saw it,
and it was in the directions of the islands, just
like he said it would be. And so Louis did
believe he was the first person to document this navigational
sign in print. Of course, it was known before him
to to the people who possessed to a part of
their navigational lore. But he believed that this phenomenon had

(37:04):
no European definition and uh. And of course, again not
all navigators in the Pacific Islands were aware of Talapa,
but some were from at least three distinct regions that
he that he interviewed navigators from, and it was interpreted
and it turned out to provide accurate information. So what
was it? What's causing these flashes of light underneath the

(37:26):
water from the direction of islands or reefs, Lewis ultimately
says in the book. And then again, this was in
seventy two, so we may have developed some knowledge since then.
But Louis said he really didn't know what it was,
and he guessed that it may have had something to
do with deep swell movement, maybe a kind of deep
reflection of waves from islands or reefs. But that leaves

(37:47):
a lot of lingering questions. Why why if it's bouncing
off of these islands or reefs, why could it be
seen at such great distances from land, albeit moving more slowly.
And one thing that I that I found so I
was reading a Harvard Gazette article about the work of
that physicist you mentioned, John Huth, who had done some
follow up work on this, and Uh. This Gazette article

(38:09):
mentioned that many scholars disputed Lewis's reports of the Tailapa quote.
The lights were initially dismissed as fantasy when other researchers
reported that they were unable to see them. Some critics
who said thought that pursuing quote underwater lightning was akin
to chasing the abominable snowman. Yeah. John Huth seems to

(38:30):
have done a fair amount of work dealing with with
Ti Lapa. And one when the source that I was
reading was the article conclusions a cross disciplinary Journey through
Spatial Orientation by who, published in the journal Structure and
Dynamics in sixteen and this he points out that there
is still no definitive explanation for the origin of Ti Lapa.

(38:53):
But one possibility that that he seems so like, is
that it's a byproduct of fish darting in a patch
of sea rich with uh dino of flageolets, which emit
light in response to the stimuli of pressure waves. But
even if that is the case, he says, then it
still leaves a mystery of the directionality of the fish
movements themselves. You know why, and how can we navigate

(39:15):
by this information? Right? What if that's the explanation why
would it point to islands in a reliable way? Right?
And Uh, one of the challenges and researching is hoothpoints
out is that the just the difficulty of rooper reproducing sightings,
we need further studies which require both sensitive equipment and
dependable sightings of the phenomena. Um and and again he

(39:38):
pointed to the fact that you don't actually see it
as a navigational aid in some cultures, uh, such as
the Marshall Islands, raising questions of you know, is this cultural?
Is it environmental? And it's simply unknown. Um. Uh so yeah,
it's it's it's really fascinating. And again it it it.
I think it serves to just remindersels, Yeah, we're dealing

(39:59):
with the suite of different navigational techniques and and if
this is among the tools at your disposal, then you know,
perhaps it is useful in in deciding like fine tuning
your your your directional approach. But perhaps for some of
some cultures they abandon it because it did not seem

(40:20):
useful enough. We just don't know. I mean, I'm pretty
convinced that people are actually observing this, that it's not
just a fantasy. And I mean not only because it
is part of the navigational lore and seems to have
been used as this backup method of direction finding. But
also because I mean, there are additional modern reports of
people saying, yeah, I actually did see it, even if
I was not able to photograph it. For example, I

(40:42):
found an article by a scholar named Marianne George who
is a cultural anthropologist who uh talks about this in
an article called Polynesian Navigation and Ta Lapa the Flashing
published in Time and Mind, the Journal of Archaeology, Consciousness,
and Culture from twelve and she also talks about having
been able to eventually witness it herself out on the ocean.

(41:05):
But I don't think you can find video of it.
I don't think anybody has ever captured it like that,
So it's still a very interesting question. Than now, one
of the really interesting things concerning all of this again
is the idea that in modern times, reacher researchers have

(41:26):
had to fit a lot of this back together, you know,
depending on genetics and linguistics and oral histories, etcetera, all
these various disciplines and as discussed in multiple places, but
specifically you see this discussed at the Bishop Museum both
the physical museum and the online presence. You also see
a discussed at at the website for Hokulea. UH. That's

(41:49):
how that's um Ata dot com. That is h O
k U l E H plus v. A is that
you saw something rather interesting concerning deep sea voyages in
Hawaiian culture. And I believe I mentioned this is one
of the previous episodes, and that is that deep sea
voyages in Hawaii had been extinct for several hundred years. Uh.
This was before contact with Europeans. The period of long

(42:12):
voyages ended along with all contact with other Polynesian islands,
and they lived in near complete isolation until seventeen seventy eight.
Now there remained memories of the the age of long
voyages and stories of their origins, of of the the
origin of the Hawaiian people um and their waves of
migration from Tahiti, which is two thousand, five hundred miles away.

(42:33):
But again, the exact art of deep sea voyages had
not been practiced for quite some time. Meanwhile, some Europeans
formed their own ideas about how humans could have possibly
made it out to such far flung islands. We mentioned
this uh in passing. You know the idea that it
was surely, surely by accident that these ancient sailors made
their way to these various islands, right, the idea that

(42:54):
new islands would have always been discovered and initially colonized
by people who got lost, were you know, blown away
in storms, random drifts basically, and again, modern scholarships has
turned away from that idea that, of course there would
probably be some cases of islands being discovered by accident,
but also a lot of cases of deliberate exploratory ventures.
Now there are also some outliers such as thor hair

(43:17):
dolls hypothesis that South American sailors made the voyage. He
famously tried and failed to prove this. But yeah, the
predominant theory for a long time with the Polynesian sailors
just simply didn't have the skill to make the journey
and they either rode the wind currents and or were
blown off course and arrived at the Hawaiian islands by accident.
But then in nineteen seventy three, the Polynesian Voyaging Society

(43:39):
formed to challenge this theory. Uh Dr Ben of Finny
Herb Collinui Kane and Tommy Holmes aimed to put together
a team to build a traditional deep sea voyaging Hawaiian
canoe and sail it from the Hawaiian Islands to Tahiti. Now,
one of the challenging parts in all this was simply
finding a traditional sailing mass. Again, especially when you're dealing

(44:01):
with Hawaiian culture, this is this is something of a
forgotten science at the uh so it had not been
practiced in a while. So they ended up going with
a particular individual by the name of of maut Paie
long Um who lived nineteen thirty two through two thousand ten,
a man from the Micronesian island of Sodawall. He'd been

(44:22):
trained from an early age and the traditional techniques of
of navigation environmental navigation, and he proved an essential part
of this whole experiment and is still remembered as a
major figure both in the academic exploration of of Hawaiian history,
Polynesian history, uh and and Oceanic culture, but also just
a sort of something of a cultural hero as well.

(44:43):
So the story of of Hoka is really fascinating and
they've been whole documentaries about it. They have a wonderful website,
But essentially they build a sixty two ft long, nineteen
foot wide double holed canoe or waakula and they called
it um. They called the vessel um hokule uh named
for an important navigational star. It's the star of Gladness,

(45:04):
also known as our Tourists and the brightest star in
the Boaties constellation. While the ship's construction also made use
of plywood, fiberglass and resin UH and it was accompanied
by a modern vessel, um Klea itself was completely unpowered,
and even more importantly, navigation was attempted without the use
of any technology or devices, at least on the way

(45:27):
to Tahiti. Um for the return trip, they did use
some instruments, uh, but they just yeah, they depended on
the traditional navigation practices that maultpie Loon brought with him.
And so on May one six they set out from
Honolulu Bay on Maui and traveled thirty three days UH
to Papa Atta Harbor in Tahiti. And they also brought

(45:48):
along with them livestock to study how these could be
cared for at sea, because as we mentioned, you know,
canoe species were a key part of the equation. It's
not just could you could you voyage to this eye
land or these islands, but could you bring the species
with you that you needed to survive? Yeah, and and
it was a success. Again, they did use instruments on

(46:09):
the return trip, but at that point they had already
proved what was possible, and multiple voyages have been completed
since then to further prove all of this out. Now,
an interesting wrinkle in all of this um is that
during the ninety nineties, the Bishop Museums Native Hawaiian Arts
and Culture Program, they set out to create an authentic
version of this sort of vessel using only traditional and

(46:29):
native material. So again you know, not the fiberglass and
so forth. But they said, let's build one like would
have been built um historically. And they found that the
native CoA trees of the islands were too small due
to human activities, so they ultimately that they had to
they had to go beyond the islands in order to
get the wood to build the canoe. They were ultimately

(46:50):
gifted four hundred year old spruce logs from a tribe
in southeast Alaska and use those to construct the vessel. Yeah.
So anyway, I I I highly recommend looking into the
Hocal Layout project. Their website, various documentaries about what they
did and and and continue to do. I thought it
is my understanding that the vessel was still functional, still operational,

(47:13):
and they still uh they still take it out. This
whole series has been one of those uh episodes on
the show where I'm just amazed because I, uh, this
is something I knew absolutely nothing about to start with.
I would not have known the very first thing about
like how you navigate on the open sea without instruments.
I mean to be honest, I don't know how you
do it with instruments either, but but uh, but yeah,

(47:36):
this is this has been so eye opening, uh, just
thinking about like how much information you can get from
the environment if you know, if you've when you build
on the knowledge accumulated over generations and you have the
discipline and the attention to pay attention to your surroundings
with this level of care. Yeah, as certainly as as
a landsman, as Hermon and Melville would put it. And

(47:59):
then is by all this, but but I think it's
also worth with pointing out that you know, we've touched
on experienced sailors who have been very into this topic
as well, have been amazed by it as well so,
uh yeah, there's there's a lot to marvel at here.
All right. Well, there you have it. We hope you
have enjoyed this journey if we've enjoyed a researching and
discussing it. If you would like to listen to other

(48:19):
episodes of Stuff to Blow your Mind, you can find
them in the Stuff to Blow your Mind podcast feed
which you're good wherever you get your podcast. Core episodes
air on Tuesdays and Thursdays. We run a short form
artifact on Wednesday's listener Man on Monday's. On Friday's we
do Weird How Cinema. That's our time to set aside
the science and the culture for the most part and
talk about a weird picture. And then we have on
the weekends a rerun. But yeah, just to find us

(48:43):
wherever you get your podcast, You can also go to
stuff to Blow your Mind dot com and that will
shoot you to the I heart listing for our page
wherever you go if they give you the power to
do so, just rate, review and subscribe huge things As
always to our excellent audio producer Seth Nicholas Johnson. If
you would like to get in touch with us with
feedback on theisode or any other to suggest topic for
the future, just to say hello. You can email us

(49:04):
at contact at stuff to Blow your Mind dot com.
Stuff to Blow Your Mind is production of I Heart Radio.
For more podcasts for my heart Radio, visit the i
heart Radio app, Apple Podcasts, or wherever you listening to
your favorite shows.