WEBVTT - Ancient Pacific Navigation, Part 3 0:00:03.040 --> 0:00:05.280 Welcome to Stuff to Blow Your Mind, the production of 0:00:05.320 --> 0:00:14.720 My Heart Radio. Hey, welcome to Stuff to Blow Your Mind. 0:00:14.840 --> 0:00:17.400 My name is Robert Lamb and I'm Joe McCormick, and 0:00:17.400 --> 0:00:20.200 we're back with part three of our series about ancient 0:00:20.280 --> 0:00:24.360 Pacific island navigation. In the previous couple of episodes, of course, 0:00:24.360 --> 0:00:25.960 if you haven't listened to those, you should go back 0:00:25.960 --> 0:00:28.400 and check those out first so you can understand what 0:00:28.400 --> 0:00:30.240 we're talking about today. But in the last couple of 0:00:30.280 --> 0:00:33.279 episodes we talked about a lot of these fascinating mysteries 0:00:33.320 --> 0:00:37.720 about the population of the Pacific Islands and and how 0:00:37.760 --> 0:00:41.000 those islands were first colonized by humans, how people found them, 0:00:41.000 --> 0:00:43.400 and then how people traveled between them once they knew 0:00:43.400 --> 0:00:45.880 where all the islands were. Because, of course, this is 0:00:45.960 --> 0:00:49.280 a huge area of the surface of the Earth that 0:00:49.400 --> 0:00:52.839 is covered almost entirely by water, and only polka dotted 0:00:52.880 --> 0:00:55.960 with these tiny islands here and there. And yet somehow, 0:00:56.040 --> 0:01:00.000 without charts, without instruments like a like a compass um, 0:01:00.080 --> 0:01:03.600 the navigators of the Pacific Islands were able to reach 0:01:03.720 --> 0:01:06.520 the other islands in in the surrounding areas with this 0:01:06.560 --> 0:01:09.560 amazing level of accuracy. So in the first episode we 0:01:09.640 --> 0:01:12.800 talked about some of the history theories about the history 0:01:12.840 --> 0:01:15.000 of the settlement of these islands, and then in the 0:01:15.080 --> 0:01:18.480 last episode we talked about techniques that have been documented 0:01:18.520 --> 0:01:23.400 that allowed master navigators to locate and and sail to 0:01:23.920 --> 0:01:28.080 islands in this in this vast ocean with enough accuracy 0:01:28.160 --> 0:01:30.600 that they could do so reliably over and over again. 0:01:30.640 --> 0:01:34.400 And what those techniques without charts and modern instruments would 0:01:34.440 --> 0:01:38.520 have been. Yeah, this this whole realm of environmental navigation, 0:01:38.640 --> 0:01:41.320 which I just want to drive home again when we're 0:01:41.319 --> 0:01:43.759 talking about this, we're talking not about some sort of 0:01:43.959 --> 0:01:47.000 innate art or something that is just uh, this one 0:01:47.040 --> 0:01:49.720 acquires by you know, being out in the water or 0:01:49.800 --> 0:01:52.360 being uh, you know, growing up on the ocean, that 0:01:52.400 --> 0:01:55.120 sort of thing. Now, this was this was a science 0:01:55.360 --> 0:01:59.000 that was learned that was passed down from generation to 0:01:59.120 --> 0:02:03.920 generation across these these different Pacific cultures. That's right. One 0:02:03.920 --> 0:02:06.000 of the main sources we've been referring to is a 0:02:06.080 --> 0:02:08.799 very important book in the history of of studying these 0:02:08.840 --> 0:02:12.160 techniques that was by a scholar named David Lewis, and 0:02:12.240 --> 0:02:15.200 it was published with the University of Hawaii Press in 0:02:15.280 --> 0:02:18.160 nineteen seventy two. It's called We the Navigators, The Ancient 0:02:18.240 --> 0:02:21.240 Art of Land Finding in the Pacific. And one thing 0:02:21.280 --> 0:02:24.120 that's really really cool about this book is that Lewis 0:02:24.760 --> 0:02:28.640 sailed well. He he interviewed many master navigators of different 0:02:28.680 --> 0:02:32.720 Pacific islands in Micronesia and Polynesia, but he also sailed 0:02:32.800 --> 0:02:37.320 with several navigators including UH, two very prominent navigators named 0:02:37.360 --> 0:02:40.959 Hippur and Tevak, from whom he learned a whole lot 0:02:41.040 --> 0:02:44.040 about these these techniques firsthand at sea, like they were 0:02:44.120 --> 0:02:47.799 navigating his boat, which was a boat called the Ispiorn 0:02:48.680 --> 0:02:51.320 and UH, and so we got to see these techniques firsthand. 0:02:51.360 --> 0:02:53.680 And so in the last episode we talked mostly about 0:02:54.160 --> 0:02:58.880 techniques for navigation on the open sea. Direction finding, so 0:02:59.040 --> 0:03:03.040 especially using the stars to to orient towards your targets 0:03:03.560 --> 0:03:06.280 and UH, and then using backup methods as well, such 0:03:06.280 --> 0:03:09.880 as like using the sun during the daytime and navigating 0:03:09.960 --> 0:03:14.720 by directionally reliable C swells, which was especially astounding to me, 0:03:14.840 --> 0:03:16.679 like the idea that you, you know, you could learn 0:03:16.720 --> 0:03:19.560 how to feel for certain patterns of C swells that 0:03:20.160 --> 0:03:22.960 reliably come from a certain direction and then use that 0:03:23.000 --> 0:03:26.560 to know which way you're heading. UM, and then also, 0:03:26.639 --> 0:03:28.960 of course, you would have to pair these direction finding 0:03:29.000 --> 0:03:32.120 techniques on the open sea with the system of dead reckoning, 0:03:32.200 --> 0:03:35.840 which is knowing how far you have traveled based on 0:03:36.080 --> 0:03:39.800 your rate of travel, your starting position, and your direction 0:03:39.840 --> 0:03:42.560 of travel and so and so. That would be a 0:03:42.600 --> 0:03:45.480 way of sort of record keeping your journey mentally as 0:03:45.520 --> 0:03:48.000 you're going along the way, even though you don't necessarily 0:03:48.040 --> 0:03:51.920 have new environmental clues to choose from. But today we 0:03:51.960 --> 0:03:55.560 wanted to get mainly into the question of land finding. 0:03:56.000 --> 0:04:00.160 So a traditional Pacific navigator has used open c navigation 0:04:00.200 --> 0:04:04.520 techniques like celestial orientation and dead reckoning to get roughly 0:04:04.600 --> 0:04:08.080 to the vicinity of an island. Once you are nearing 0:04:08.120 --> 0:04:11.960 your destination, how do you actually find the land? Yeah, 0:04:11.960 --> 0:04:13.960 because as we discussed in the previous episode, you don't 0:04:13.960 --> 0:04:16.320 want to you know, be sailing in the right direction 0:04:16.520 --> 0:04:18.400 to be in the vicinity of the island and then 0:04:18.480 --> 0:04:21.120 not be able to see it to again again not 0:04:21.200 --> 0:04:23.960 be close enough to pick up on the very obvious 0:04:24.200 --> 0:04:26.560 cues that you were near the island, and have to 0:04:26.560 --> 0:04:29.719 pick up on those more subtle cues that would require 0:04:29.760 --> 0:04:33.240 training and expertise to notice. Right, I mean, one of 0:04:33.279 --> 0:04:38.159 the biggest dangers actually for a Pacific island sailor is missing, 0:04:38.200 --> 0:04:41.279 your target is going past the island you're trying to 0:04:41.279 --> 0:04:44.600 get to without realizing it. Yeah, I mean, in a 0:04:44.720 --> 0:04:49.159 very very loose sense, it's like depending on say, your 0:04:49.760 --> 0:04:53.440 your GPS navigational system, which we refer to previously, you know, 0:04:53.839 --> 0:04:57.560 using that to get to the immediate area, like the 0:04:57.600 --> 0:05:01.119 block where the where the or is that you're trying 0:05:01.120 --> 0:05:03.200 to go a story you've never been to before. But 0:05:03.240 --> 0:05:05.640 then once you're there, the GPS is only gonna help 0:05:05.680 --> 0:05:07.919 you so much. Then you're gonna have to pinpoint the sign, 0:05:07.960 --> 0:05:10.960 figure out which storefront it is, figure out your parking, etcetera. 0:05:10.960 --> 0:05:13.840 There are a whole new set of problems that your 0:05:13.880 --> 0:05:18.440 mirror navigational system, your GPS, is not able to help 0:05:18.440 --> 0:05:21.760 you with. Right. And so, one thing that's very interesting 0:05:21.839 --> 0:05:25.440 that David Lewis explores in his book is what he 0:05:25.480 --> 0:05:30.400 calls the idea of expanded target landfall. And what that 0:05:30.440 --> 0:05:35.400 means is that by using a suite of land finding techniques, 0:05:35.720 --> 0:05:40.799 you can essentially extend the radius of land a certain 0:05:41.480 --> 0:05:44.560 reliable distance out into the ocean. And I'll talk about 0:05:44.560 --> 0:05:47.200 the distances as we go on, but there's a certain 0:05:47.240 --> 0:05:50.000 reliable distance out into the ocean that you can just 0:05:50.120 --> 0:05:53.160 expect to be able to detect nearby land even if 0:05:53.200 --> 0:05:57.600 you can't see it. And if you measure land, including 0:05:57.680 --> 0:06:01.520 those radii out into the ocean beyond the shore and 0:06:01.720 --> 0:06:04.919 h and especially beyond sort of like reefs and submerged 0:06:05.080 --> 0:06:09.000 or or almost submerged a toolls nearby, you can actually 0:06:09.760 --> 0:06:14.360 greatly expand the percent of the Pacific Ocean that is 0:06:14.440 --> 0:06:18.839 taken up by by by land range. Basically, so you 0:06:18.880 --> 0:06:23.320 can expand your target from these tiny islands surrounded mostly 0:06:23.360 --> 0:06:28.039 by water to basically a block of islands with mostly 0:06:28.200 --> 0:06:33.240 or totally overlapping ranges of land detectable water. Does that 0:06:33.279 --> 0:06:40.560 make sense? Yes, yeah, basically increases the the the footprint 0:06:40.760 --> 0:06:45.120 of the island, like the the detectable footprint of the island. Right. So, so, 0:06:45.160 --> 0:06:48.960 of course the direction finding techniques like celestial navigation are 0:06:49.000 --> 0:06:51.960 extremely important and getting you towards your your target, but 0:06:52.040 --> 0:06:55.800 also the expanded target landfall is just as important, if 0:06:55.800 --> 0:06:57.599 not more important. I mean, I guess you can't really 0:06:57.640 --> 0:07:00.680 have one without the other. It is also extremely important 0:07:01.560 --> 0:07:04.760 because you know, there's only so accurate you can get 0:07:04.839 --> 0:07:07.560 with steering by stars, you still need to be able 0:07:07.640 --> 0:07:11.040 to correct course and find the land once you're close enough. 0:07:11.800 --> 0:07:14.720 And so, how far exactly can you expect to find 0:07:14.880 --> 0:07:17.840 land from out in the ocean. Well, it does very 0:07:17.880 --> 0:07:20.960 a lot, depending on local conditions. But Lewis cites a 0:07:21.000 --> 0:07:25.120 scholar named Frankel who estimates that on average, land can 0:07:25.240 --> 0:07:28.880 usually be detected from about thirty miles in any direction, 0:07:29.000 --> 0:07:32.640 and Louis essentially agrees with this number. Uh, And then 0:07:32.720 --> 0:07:36.040 he writes this quote. If we draw circles with thirty 0:07:36.080 --> 0:07:39.800 miles radii around each Pacific island, we find that the 0:07:39.840 --> 0:07:44.800 circles overlap over vast areas, giving rise to solid blocks 0:07:44.800 --> 0:07:48.960 i e. Islands separated by not more than sixty miles 0:07:49.360 --> 0:07:52.240 passing between which a canoe could not be more than 0:07:52.280 --> 0:07:56.960 thirty miles offshore. So, with these expanded target landfall techniques, 0:07:57.040 --> 0:08:00.240 the problem of finding these tiny islands in the past 0:08:00.280 --> 0:08:05.320 ocean actually is much more manageable. It's reducible more to 0:08:05.600 --> 0:08:10.720 finding these blocks or screens of islands within a certain angle. 0:08:11.000 --> 0:08:14.120 You know a certain angle of direction from your starting position, 0:08:14.640 --> 0:08:17.800 So it means that what would otherwise be a sprinkle 0:08:17.840 --> 0:08:21.760 of islands becomes a clump of islands, yes, which there's 0:08:21.800 --> 0:08:23.720 some there. You actually you shared a wonderful map here 0:08:23.760 --> 0:08:27.240 that that that demonstrates this, and it's really it's really 0:08:27.320 --> 0:08:30.120 quite impressive because you can see it making a huge 0:08:30.120 --> 0:08:33.440 amount of difference, uh, is you're traveling, you know, between 0:08:33.480 --> 0:08:37.199 these these islands, uh potentially even charting some of these 0:08:37.720 --> 0:08:41.360 these more distant journeys. That's right. So if you're looking 0:08:41.360 --> 0:08:45.200 at it from a map that includes expanded target landfall 0:08:45.240 --> 0:08:47.520 as sort of a black circle around the island, what 0:08:47.640 --> 0:08:50.640 would have been a smattering of of little tiny dots 0:08:50.679 --> 0:08:55.320 instead turns into a big clump of black circles that 0:08:55.520 --> 0:08:58.880 they're all overlapping each other. So this really does help 0:08:58.880 --> 0:09:01.439 with the problem. But of course you you could easily 0:09:01.480 --> 0:09:04.959 once again pass between these islands without actually being able 0:09:05.000 --> 0:09:07.760 to see them visually. So you need to be able 0:09:07.840 --> 0:09:10.400 to know what to look for. And again one of 0:09:10.440 --> 0:09:13.360 the things that stressed, especially in we the navigators, is 0:09:13.440 --> 0:09:18.120 that the degree of what they call screening the screening 0:09:18.120 --> 0:09:21.520 of islands rather than individual island targets. So you would 0:09:21.520 --> 0:09:24.400 aim for a screen like a line of islands that 0:09:24.440 --> 0:09:28.200 are all overlapping within land finding range of one another. 0:09:28.840 --> 0:09:32.640 That the the degree of screening of an island or 0:09:32.679 --> 0:09:36.640 island group target was the number one safety concern when 0:09:36.679 --> 0:09:40.400 making a journey there, So more screening more overlapping of 0:09:40.480 --> 0:09:44.160 the expanded targets is safer, and less screening where there 0:09:44.200 --> 0:09:48.000 are gaps between the expanded targets is much more dangerous 0:09:48.440 --> 0:09:51.640 because again of the danger of unknowingly passing your target. 0:09:52.000 --> 0:09:53.800 But I guess we should talk about what are the 0:09:53.840 --> 0:09:57.680 actual landfall signs? What are the environmental signs that can 0:09:57.720 --> 0:10:00.840 be used to detect a land from a long distance away. 0:10:01.640 --> 0:10:03.680 I guess we should start with the one that is 0:10:03.720 --> 0:10:05.960 the most obvious. Maybe this one doesn't actually need to 0:10:05.960 --> 0:10:07.720 be said, but there are a couple of things about 0:10:07.720 --> 0:10:10.440 it that are worth sorting out. Actually, So the most 0:10:10.480 --> 0:10:13.880 obvious one is high ground. Right. In some cases your 0:10:13.920 --> 0:10:16.520 target island is very tall and it can be seen 0:10:16.559 --> 0:10:20.239 from very far away. So, for example, Tahiti reaches elevations 0:10:20.240 --> 0:10:23.720 of something like seventy feet and for this reason, the 0:10:23.840 --> 0:10:26.440 land itself can sometimes be seen from as far as 0:10:26.520 --> 0:10:30.280 eighty miles away. That that's a real good distance. And likewise, 0:10:30.280 --> 0:10:33.080 Hawaii that can be seen from extremely far away. It 0:10:33.120 --> 0:10:36.920 contains volcanoes, and rising land mass that sometimes up up 0:10:36.960 --> 0:10:40.600 to like thirteen thousand feet, but not every island is 0:10:40.640 --> 0:10:43.840 tall like this. Many Pacific islands lie more or less 0:10:43.840 --> 0:10:47.200 at sea level, with nothing much taller than the height 0:10:47.200 --> 0:10:49.760 of a palm tree, and you can easily miss these. 0:10:50.040 --> 0:10:54.760 Standard navigational lore holds that on these low islands, visibility 0:10:54.800 --> 0:10:58.520 is about ten miles, given the presence of coconut palms, 0:10:58.800 --> 0:11:01.240 which grow to about of any five feet high, so 0:11:01.280 --> 0:11:03.480 at about ten miles you should be able to see 0:11:03.720 --> 0:11:07.120 the tallest of the coconut palms. It's interesting. I was 0:11:07.160 --> 0:11:09.840 reading about about this and it reminded me of our 0:11:09.880 --> 0:11:12.040 episode on on the Font of Morgana, where we talked 0:11:12.040 --> 0:11:15.240 about mirages and about how in some cases there were 0:11:15.440 --> 0:11:18.520 islands that we even put on maps that turned out 0:11:18.559 --> 0:11:22.199 to not be real. They were based on on mirrages. 0:11:22.720 --> 0:11:25.480 And the reverse of that is also true. There are 0:11:25.600 --> 0:11:30.280 islands that um certainly as as European powers were coming 0:11:30.280 --> 0:11:32.400 into play and trying to map everything out, there were 0:11:32.480 --> 0:11:36.440 islands that were that were known to be to exist 0:11:37.320 --> 0:11:41.800 by by the natives, but various Europeans would would have 0:11:41.800 --> 0:11:44.200 would decide, well, this was probably a mirage. We don't have. 0:11:44.559 --> 0:11:46.679 We don't know exactly where it is, but it would 0:11:46.679 --> 0:11:49.240 turn out it was actually there. Yeah, and it's funny 0:11:49.240 --> 0:11:52.960 you should bring up the Fedamorghana episode because this land 0:11:53.000 --> 0:11:56.560 finding technique is way down the list in terms of 0:11:56.559 --> 0:11:59.560 of how commonly it was used in the level of 0:11:59.559 --> 0:12:02.880 priori it's given. But one of the things mentioned in 0:12:02.920 --> 0:12:06.480 this book is that land loom, the optical illusion of 0:12:06.520 --> 0:12:08.640 being able to see the land in a in a 0:12:08.679 --> 0:12:13.240 superior mirage projected up above the horizon, even though the 0:12:13.320 --> 0:12:16.160 land is not visible itself from where you are. This 0:12:16.240 --> 0:12:20.480 actually was sometimes used by some Pacific Island navigators, specifically 0:12:20.559 --> 0:12:24.400 Lewis Sites navigators from the Gilbert's using this one. But 0:12:24.679 --> 0:12:28.000 coming back to the idea of vantage points and high ground, 0:12:28.760 --> 0:12:32.040 there is actually a pretty reliable mathematical equation you can 0:12:32.120 --> 0:12:35.640 use for determining the visibility of an object over the 0:12:35.679 --> 0:12:38.800 horizon at sea uh and and it goes like this, 0:12:39.320 --> 0:12:42.080 So you take the square root of the height of 0:12:42.120 --> 0:12:45.600 the object you're looking for in feet and and so 0:12:45.679 --> 0:12:48.440 this is this method will be unit dependent, but the 0:12:48.480 --> 0:12:50.720 square root of the height of the object and feet 0:12:51.040 --> 0:12:52.760 so that could be a you know, a seventy five 0:12:52.800 --> 0:12:55.280 foot tall palm tree, or it could be a mountaintop 0:12:55.360 --> 0:12:58.520 or a lighthouse, whatever that is. And then you add 0:12:58.600 --> 0:13:02.160 that to the square route of the observer's height, so 0:13:02.240 --> 0:13:04.120 that would also be in feet. If you're you know, 0:13:04.160 --> 0:13:06.480 if your eyes are five feet above the water, that's 0:13:06.520 --> 0:13:09.040 five feet, or if you're sitting down in a low canoe, 0:13:09.080 --> 0:13:12.040 it's probably even lower. And then you you add those 0:13:12.080 --> 0:13:15.800 together and then you multiply by I've seen different numbers. 0:13:15.840 --> 0:13:19.920 Actually I found a navigational website that suggested multiplying that 0:13:20.000 --> 0:13:23.760 number by one point one seven. Lewis gives gives the 0:13:23.800 --> 0:13:27.320 idea to multiply by one point one five. But whichever 0:13:27.360 --> 0:13:29.320 way you do, you'll probably get pretty close to the 0:13:29.360 --> 0:13:33.240 same answer, and this will give you the distance away 0:13:33.360 --> 0:13:36.560 in miles that an object can usually be seen over 0:13:36.559 --> 0:13:39.920 the horizon. But that made me think about the height 0:13:40.040 --> 0:13:43.480 of the observer, which makes me wonder about the land 0:13:43.559 --> 0:13:48.439 finding virtues of different watercraft, right, because they're obviously different 0:13:48.480 --> 0:13:51.000 kinds of watercraft. People make these journeys and sometimes there 0:13:51.040 --> 0:13:53.880 in they could be in outrigger canoes or they could 0:13:53.920 --> 0:13:58.240 be in a double hulled traditional navigational vessel that would 0:13:58.280 --> 0:14:00.960 have a much more raised form in the middle with 0:14:01.000 --> 0:14:03.280 even a cabin that I guess you could technically get 0:14:03.320 --> 0:14:05.920 on top of. I don't know how, I don't know 0:14:05.960 --> 0:14:09.439 what all of the techniques with with ancient Pacific watercraft 0:14:09.480 --> 0:14:11.720 would be for getting higher up as a vantage point. 0:14:11.760 --> 0:14:13.679 But that seems like that that could give you an 0:14:13.679 --> 0:14:16.840 advantage as well, right, because of course they would not 0:14:16.920 --> 0:14:20.320 have the advantage that that you would have with agin 0:14:20.360 --> 0:14:24.560 a crow's nest lookout in a in a western sailing vessel, 0:14:24.600 --> 0:14:29.120 like you know, a large scale ocean voyaging ship. That's right. 0:14:29.280 --> 0:14:33.800 But uh, fortunately, these these specific navigators had lots of 0:14:33.800 --> 0:14:37.400 other environmental cues they could look for. And these cues 0:14:37.440 --> 0:14:40.360 are very important because even with taller islands, so even 0:14:40.400 --> 0:14:41.960 if you're trying to get, you know, to a place 0:14:42.000 --> 0:14:44.520 that's mountainous, you're trying to get to Tahiti or Hawaii 0:14:44.600 --> 0:14:49.680 or something, environmental conditions can render these less visible. So 0:14:49.800 --> 0:14:54.240 Louis gives the example of mountains, the mountains of Mangareva 0:14:54.320 --> 0:14:57.320 and truck which should be visible based on their height 0:14:57.400 --> 0:15:00.560 from like forty five miles away, but he says that 0:15:00.840 --> 0:15:03.800 in his case, when he was once approaching in in 0:15:03.880 --> 0:15:06.400 the boat, they were unable to see the peaks of 0:15:06.440 --> 0:15:10.120 these islands because of overcast, and so their first visual 0:15:10.160 --> 0:15:13.160 sighting was actually of the surrounding barrier reef rather than 0:15:13.200 --> 0:15:15.920 of the island itself. Now, as we go on to 0:15:15.960 --> 0:15:18.720 discuss more of these land finding techniques, it's important to 0:15:18.800 --> 0:15:22.360 note that they vary in both directions, meaning that the 0:15:22.480 --> 0:15:26.760 land finding techniques very in preference of individual navigators and 0:15:26.880 --> 0:15:31.920 navigator cultures and in availability at target. So there are 0:15:31.960 --> 0:15:35.320 some like, uh, there's some traditions of land finding lore 0:15:35.800 --> 0:15:38.320 that place more emphasis on one or the other. But 0:15:38.440 --> 0:15:41.360 also you need to have the backup knowledge because you're 0:15:41.360 --> 0:15:43.560 not always going to be able to find all of 0:15:43.600 --> 0:15:45.680 these when you look for them. Yeah, again, this is 0:15:45.680 --> 0:15:48.160 a suite of tools that one that a navigator would use. 0:15:48.200 --> 0:15:51.120 This is a toolbox of different techniques, and you're not 0:15:51.160 --> 0:15:53.360 gonna want to depend on just one of them. Now, 0:15:53.360 --> 0:15:55.360 you're gonna use several of them, and some of them 0:15:55.360 --> 0:15:58.840 are gonna better than others. But when used in congress, 0:15:58.880 --> 0:16:03.000 you can get the train navigator can get really positive results. Now, 0:16:03.000 --> 0:16:05.640 there's one thing that Lewis mentions in this book which 0:16:05.640 --> 0:16:07.960 I thought was interesting, which is a sort of counter 0:16:08.080 --> 0:16:11.120 example to uh. The thing we've talked about a couple 0:16:11.200 --> 0:16:13.080 a couple of times, which is that he says, you know, 0:16:13.240 --> 0:16:15.920 none of the navigators he spoke to or traveled with 0:16:16.600 --> 0:16:19.560 ever ever appealed to the idea of a sixth sense. 0:16:19.680 --> 0:16:22.520 Right you were mentioning this earlier, it's not just intuition 0:16:22.600 --> 0:16:26.440 about being at sea. When they were making navigational decisions, 0:16:26.440 --> 0:16:30.000 they could always point to specific markers. They could say 0:16:30.080 --> 0:16:32.440 the reason I'm going this way is because of this. 0:16:32.560 --> 0:16:35.440 It's something that was in the environment that could be 0:16:35.560 --> 0:16:38.680 pointed out and understood. So it wasn't just a gut feeling. 0:16:39.200 --> 0:16:42.160 But one place in which he does say intuition seemed 0:16:42.200 --> 0:16:45.360 to come in was in the calculus of how much 0:16:45.440 --> 0:16:50.600 to wait different types of observations of of land finding signs. 0:16:50.640 --> 0:16:53.440 So navigators might get close to an island and you'd 0:16:53.440 --> 0:16:56.360 see one kind of sign and then another one, and 0:16:56.400 --> 0:16:59.400 they'd be trying to decide which way to go based 0:16:59.440 --> 0:17:03.800 on maybe different conflicting signals, or or what what the 0:17:04.160 --> 0:17:06.879 sort of sum total or average of the evidence was. 0:17:07.040 --> 0:17:09.159 And that did seem to be more based on a 0:17:09.200 --> 0:17:12.440 gut feeling after surveying all the evidence available to them. 0:17:12.720 --> 0:17:20.280 So I thought that was an interesting counterpoint. Thank thank 0:17:20.560 --> 0:17:23.560 thank so. The first big sign to mension, I think 0:17:23.600 --> 0:17:27.640 would be birds. Uh. There's actually a part where where 0:17:27.720 --> 0:17:32.320 Lewis sites a navigator named Tita who says that who 0:17:32.480 --> 0:17:34.760 is quoted at length on this. He says birds are 0:17:34.800 --> 0:17:38.359 the navigator's very best friends. Birds are useful up to 0:17:38.440 --> 0:17:40.959 twice the site range of an island from a canoe. 0:17:41.760 --> 0:17:44.119 And he also says the site range of land is 0:17:44.160 --> 0:17:47.840 about ten miles and that of birds twenty. The birds 0:17:47.840 --> 0:17:52.440 which are the most significant are turns and noddies. Yeah, 0:17:52.480 --> 0:17:53.800 I've read that. Yeah. A lot of it comes down 0:17:53.840 --> 0:17:56.240 to familiarity with bird species. It's not just, of course 0:17:56.240 --> 0:18:00.360 birds in general, but specific knowledge of how are out 0:18:00.400 --> 0:18:04.200 to see a particular bird species will typically go So 0:18:04.280 --> 0:18:06.240 if it's a if it's a sea bird, for instance, 0:18:06.280 --> 0:18:09.080 the distance could be somewhere in the neighborhood of a 0:18:09.160 --> 0:18:15.840 hundred kilometers, which is about sixty two point one miles. Um. 0:18:15.880 --> 0:18:17.679 You know, again, it's just going to depend on the 0:18:17.720 --> 0:18:22.240 exact variety of bird, uh, while other varieties of bird 0:18:22.280 --> 0:18:25.160 are going to stay much closer to land. That's right. 0:18:25.200 --> 0:18:27.720 So yeah, you need to look not just for birds 0:18:27.720 --> 0:18:32.080 in general, but for specific species of birds, because there are, 0:18:32.119 --> 0:18:35.919 as you mentioned, pelagic species like petrolls and sheer waters 0:18:35.920 --> 0:18:38.960 that will just not lead you to land with any reliability. 0:18:39.000 --> 0:18:41.560 If you follow them, you may end up cruising out 0:18:41.600 --> 0:18:44.679 into the deep and not coming back. But once you 0:18:44.680 --> 0:18:48.159 get within about thirty to fifty miles of shore, you 0:18:48.240 --> 0:18:51.960 will start to see some familiar species that are somewhat reliable. 0:18:52.240 --> 0:18:55.399 So first of all, you'll see booby birds uh and 0:18:55.520 --> 0:18:58.840 sometimes predatory frigate birds. At this distance of thirty to 0:18:58.960 --> 0:19:02.520 fifty miles, and then even closer, within about twenty to 0:19:02.600 --> 0:19:05.600 twenty five miles of the nearest a toll, you will 0:19:05.640 --> 0:19:09.280 get what what Louis says are quote mixed flocks of 0:19:09.400 --> 0:19:13.320 white turns and noddies that will be encountered busily searching 0:19:13.359 --> 0:19:16.479 for fish. And once again, they show no more interest 0:19:16.560 --> 0:19:19.719 in directing the wayfarer than a busy New York policeman. 0:19:20.720 --> 0:19:23.399 Uh So, so there's some further deduction you have to do. 0:19:23.440 --> 0:19:25.199 It's not just like you see the birds and then 0:19:25.240 --> 0:19:28.160 you immediately know what's up. If you see booby birds, 0:19:28.160 --> 0:19:31.440 frigate birds, turns and naughties, you know you're close, but 0:19:31.600 --> 0:19:35.160 you can't really use their flight paths and behavior throughout 0:19:35.160 --> 0:19:38.240 the daytime to know which direction land lies. So what 0:19:38.280 --> 0:19:41.959 do you do. Well, you have to use time of day. 0:19:42.119 --> 0:19:45.120 These species roost on land and they have to return 0:19:45.160 --> 0:19:47.960 to solid ground daily, and so the time of day 0:19:48.000 --> 0:19:50.400 tells you a lot. They typically fly out to their 0:19:50.400 --> 0:19:53.479 fishing shoals from land in the early morning, and then 0:19:53.520 --> 0:19:56.480 they return to land in the evening. So to read 0:19:56.520 --> 0:20:00.520 a passage from from Louis here he writes quote towards evening, 0:20:00.520 --> 0:20:03.440 the frigate birds, for example, will be seen to abandon 0:20:03.480 --> 0:20:07.000 their leisurely patrolling, climb even higher, and set off in 0:20:07.000 --> 0:20:10.920 one direction, probably homing by sight. About the same time, 0:20:11.000 --> 0:20:14.200 the boobies will tire of their inquisitive inspections and fly 0:20:14.400 --> 0:20:18.479 low and arrows straight for the horizon. As the noddies depart, 0:20:18.600 --> 0:20:21.360 they will weave slightly in and out between the crests 0:20:21.359 --> 0:20:24.119 of larger waves, while the turns will be flying a 0:20:24.160 --> 0:20:27.120 little above them, but all will be following a very 0:20:27.200 --> 0:20:31.080 exact path towards their home island. So once you are 0:20:31.160 --> 0:20:33.280 within range of land, and you've gotten there again by 0:20:33.280 --> 0:20:36.800 the process of of of open sea navigation, often by 0:20:36.840 --> 0:20:40.040 the stars, and uh, and then these backup methods together 0:20:40.080 --> 0:20:42.879 with dead reckoning, you get within range of the island, 0:20:42.920 --> 0:20:45.560 you start to see certain bird species and you know 0:20:45.640 --> 0:20:48.880 which species to look for and what time of day 0:20:48.920 --> 0:20:51.680 to follow them. And if you see the birds all 0:20:51.720 --> 0:20:54.720 trending in the same direction around sundown, then you know. 0:20:55.400 --> 0:20:57.440 There are also a few stories here and there about 0:20:57.600 --> 0:21:01.439 islands where some sea going birds have and domesticated, you know, 0:21:01.480 --> 0:21:04.159 like fed and trained. But these stories seemed kind of 0:21:04.280 --> 0:21:07.160 vague and uncertain, but it is at least an interesting 0:21:07.160 --> 0:21:10.159 possibility to consider, whether there's much to it or not. 0:21:10.560 --> 0:21:13.560 Like what if an island culture could essentially train frigate 0:21:13.600 --> 0:21:18.320 birds to be the walmart greeters of the island. Yeah, yeah, 0:21:18.320 --> 0:21:22.399 and almost like living lighthouses in some respects. Yeah, because 0:21:22.440 --> 0:21:25.560 the behavior of birds can factor and apart from just uh, 0:21:25.640 --> 0:21:28.560 you know, flying back like booby, birds are considered useful 0:21:28.600 --> 0:21:31.359 in that they will not only fly towards land at 0:21:31.359 --> 0:21:33.800 the close of day, they will often take an active 0:21:33.920 --> 0:21:36.720 interest in approaching boats and they will try to land 0:21:36.760 --> 0:21:39.160 on them, like land on the rigging or something, before 0:21:39.200 --> 0:21:42.119 eventually flying off toward home in the evening. Now, I 0:21:42.119 --> 0:21:44.399 know a lot of you out there probably watched The 0:21:44.440 --> 0:21:46.560 Simpsons or have watched The Simpsons in the past, and 0:21:46.600 --> 0:21:49.520 you're probably thinking about the scene in the episode Boy 0:21:49.560 --> 0:21:53.639 Scouts in the Hood. Uh uh, this is the the 0:21:53.680 --> 0:21:56.760 episode and what let's see. I'm trying to remember exactly 0:21:56.800 --> 0:21:58.960 how it went. And did they get lost at sea? Well, 0:21:59.000 --> 0:22:01.720 first they get lost at her which then results and 0:22:01.760 --> 0:22:04.040 then being lost at sea and they're trying to get 0:22:04.040 --> 0:22:06.840 back to land and then what do they see in 0:22:06.840 --> 0:22:08.760 the sky? They see a seagull. Is this the one 0:22:08.800 --> 0:22:11.239 that starts with Bart wanting a knife but to get 0:22:11.320 --> 0:22:14.040 a knife, Yeah, and he has to he has to 0:22:14.080 --> 0:22:17.520 read the book don't do what Donny Don't does. But yeah, 0:22:17.520 --> 0:22:19.840 it ends up with them doing a boy Scout river race, 0:22:19.920 --> 0:22:21.760 and so they're lost at sea and what I don't 0:22:21.800 --> 0:22:25.720 remember what happens with the seagull. I think Ned declare. 0:22:25.840 --> 0:22:27.600