WEBVTT - Invention Classic: Sun Glasses 0:00:07.360 --> 0:00:10.159 Hey, welcome to Invention. My name is Robert Lamb and 0:00:10.240 --> 0:00:12.840 I'm Joe McCormick, and today we're bringing you a classic 0:00:12.880 --> 0:00:17.520 episode of Invention. This one originally published on January seven, nineteen, 0:00:17.600 --> 0:00:20.279 and it's about sunglasses. That's right. Yeah, this is a 0:00:20.280 --> 0:00:23.320 pretty fun one because sunglasses are one of those inventions 0:00:23.320 --> 0:00:25.400 that it's easy to take for granted, and it's easy 0:00:25.480 --> 0:00:29.280 to assume that it's tied pretty much to the modern age. 0:00:29.400 --> 0:00:32.240 But y as we get into here, that's not quite 0:00:32.240 --> 0:00:45.080 the case. Hey, welcome to Invention. My name is Robert 0:00:45.159 --> 0:00:48.160 Lamb and I'm Joe McCormick. Robert, what kind of sunglasses 0:00:48.159 --> 0:00:51.440 do you wear? Well? Currently, uh, my son is six 0:00:51.520 --> 0:00:53.760 years old, so I've been going through a spell here 0:00:53.840 --> 0:00:58.400 where I can really only wear whatever kind of semi 0:00:58.440 --> 0:01:01.040 garbage swag sunglasses has come my way, you know, with 0:01:01.160 --> 0:01:05.560 various brand names plastered to the side of them, because inevitably, 0:01:05.600 --> 0:01:08.600 especially when he was younger, my son would have to 0:01:08.600 --> 0:01:11.200 get his hands on whatever kind of sunglasses I had 0:01:11.240 --> 0:01:15.120 in the car. So the sunglasses get smudged, sunglasses get 0:01:15.160 --> 0:01:19.360 scratched up, sunglasses get broken or just lost. And I 0:01:19.400 --> 0:01:22.160 was pretty good at losing sunglasses even before he came 0:01:22.160 --> 0:01:25.520 into my life. Uh So, I'm hoping that I'm working 0:01:25.600 --> 0:01:28.760 up to very soon reaching that point where I can 0:01:28.920 --> 0:01:31.800 actually buy a decent pair of sunglasses that will protect 0:01:31.880 --> 0:01:34.960 my eyes. Did you ever actually wear those company sunglasses 0:01:34.959 --> 0:01:39.680 we got? I have, like them like fold in half 0:01:39.760 --> 0:01:43.040 at the nose. Yeah, I I got those immediately. Mainly 0:01:43.080 --> 0:01:45.319 I I thought to myself, this is a great decoy 0:01:45.440 --> 0:01:48.280 brand because my son is gonna love like the Transformer 0:01:48.480 --> 0:01:51.640 s qualities of these sunglasses here break that one. Yeah, 0:01:51.800 --> 0:01:54.480 But I've ended up wearing them around anyway. So that's 0:01:54.560 --> 0:01:56.920 my story. Hopefully, by the time I'm ready to actually 0:01:57.000 --> 0:01:59.880 get some decent sunglasses, we'll have some like Back to 0:01:59.920 --> 0:02:02.600 the Future two sunglasses, you know, like the ones that 0:02:02.600 --> 0:02:05.600 you've got as a prize uh Pizza Hut back in 0:02:05.640 --> 0:02:07.760 the day when that film first came out. Except now 0:02:07.840 --> 0:02:10.720 these will be legit future sunglasses. You know. I was 0:02:10.800 --> 0:02:13.280 trying to think before we decided to do this episode, 0:02:13.320 --> 0:02:17.080 our sunglasses an invention or not? Did they count? Yeah? 0:02:17.120 --> 0:02:20.160 They count? I guess everything is an invention. Were we 0:02:20.200 --> 0:02:23.600 born with sunglasses? Well we'll get into that, but yeah, 0:02:23.600 --> 0:02:27.040 it is difficult for us to imagine a time before sunglasses. 0:02:27.440 --> 0:02:29.920 How did Corey Hart keep track of the visions in 0:02:29.919 --> 0:02:32.760 his eyes? I don't know. How did rowdy Roddy Piper 0:02:32.800 --> 0:02:36.400 see through the alien conspiracy? I guess I don't know. 0:02:36.520 --> 0:02:39.120 He didn't how to terminate or cover up his eye damage. 0:02:39.680 --> 0:02:42.120 That's a good point, bro, Really, how did anyone ever 0:02:42.680 --> 0:02:45.080 in the history of Earth managed to look cool at 0:02:45.080 --> 0:02:47.680 any given moment, much less shade their eyes from the 0:02:47.800 --> 0:02:50.280 vicious light of day. It's already telling that all the 0:02:50.360 --> 0:02:53.320 examples you point to our cultural ones you're pointing, You're 0:02:53.360 --> 0:02:56.079 pointing to movies and stuff, rather than talking about how 0:02:56.080 --> 0:02:59.240 would I get through my life without sunglasses? Well, that 0:02:59.600 --> 0:03:01.280 this is to be an important part of just the 0:03:01.639 --> 0:03:04.320 iconography of the sunglasses, and that will be more important 0:03:04.520 --> 0:03:07.320 later on in our discussion, but in their their psychological 0:03:07.320 --> 0:03:11.560 effects example in that, but initially here you know, we're 0:03:11.560 --> 0:03:14.919 we're we're complicating the purpose of the sunglasses, babe by Basically, 0:03:15.800 --> 0:03:18.320 the whole deal is the sun is bright. I disagree, 0:03:19.200 --> 0:03:21.720 And while our eyelids do give us the ability to 0:03:21.760 --> 0:03:25.160 manipulate the amount of sunlight hitting our eyeballs, it also 0:03:25.240 --> 0:03:28.280 pays to have other options and certainly we have the 0:03:28.320 --> 0:03:30.480 ability to look away from the sun, to hide from 0:03:30.480 --> 0:03:33.919 the sun, or to raise a hand or a forearm 0:03:34.000 --> 0:03:38.640 to block it. But that's dependent largely on say your environment. 0:03:38.880 --> 0:03:41.800 Like some environments are much brighter than others. What if 0:03:41.840 --> 0:03:44.640 you live in a place where, say it's springtime, and 0:03:44.720 --> 0:03:48.280 you're in a place with snow cover. The sun can 0:03:48.320 --> 0:03:50.760 be so bright in those cases because it's not only 0:03:50.760 --> 0:03:53.520 coming from above, but reflecting off of the snow, that 0:03:53.600 --> 0:03:57.680 you essentially cannot use your eyes in the environment, right, 0:03:57.720 --> 0:04:00.480 because otherwise you can't just shade where hat you need 0:04:00.520 --> 0:04:02.440 to wear like a hat with two bills right, one 0:04:02.440 --> 0:04:05.040 on top, one at the bottom. Um, it's coming from 0:04:05.080 --> 0:04:07.000 all directions, and you need to use your hands for 0:04:07.040 --> 0:04:10.320 other things. You're an individual, will need to to hunt 0:04:10.400 --> 0:04:13.560 or fish or craft, etcetera. You can't just go around 0:04:13.560 --> 0:04:17.440 with your hands up all the time. Um. When I 0:04:17.520 --> 0:04:21.640 when I think about the challenges of dealing with sunlight, 0:04:21.920 --> 0:04:24.599 and I'm always forced to just think about how amazing 0:04:24.600 --> 0:04:28.640 our eyelids are though for manipulating light well, and our 0:04:28.680 --> 0:04:31.279 iris is of course they our pupils contract when there's 0:04:31.320 --> 0:04:33.160 too much light, but there's a point at which they 0:04:33.160 --> 0:04:36.560 can't contract anymore, and you have to depend on the eyelids. 0:04:37.160 --> 0:04:39.080 One of one example I always go to is there's 0:04:39.080 --> 0:04:43.919 a character in Larry McMurtry's novel Comanche Moon and he 0:04:43.920 --> 0:04:50.880 he winds up tortured by bandit flares and they slice 0:04:50.880 --> 0:04:54.200 his eyelids off. They leave him for for dead in 0:04:54.240 --> 0:04:56.320 the sun, and he's you know, half driven mad by 0:04:56.320 --> 0:04:59.560 the whole whole ordeal but sick eyelids. Oh yeah, it 0:04:59.680 --> 0:05:02.080 is a It is a sick, weird book. Um, I 0:05:02.120 --> 0:05:06.840 love it. It's my favorite McMurtry book. But afterwards, this 0:05:06.920 --> 0:05:10.240 character ends up constructing a pair of special sunglasses for 0:05:10.320 --> 0:05:16.840 himself with these varying, um varying levels of darkness, so 0:05:16.880 --> 0:05:18.760 that he can just click through them as he needs them, 0:05:18.800 --> 0:05:21.080 depending on where he is, if he's a you know, 0:05:21.160 --> 0:05:25.719 indoors outdoors, bright day, uh, you know, cloudy day, etcetera. 0:05:26.080 --> 0:05:28.360 But I always come back to that because it's like, yeah, 0:05:28.360 --> 0:05:31.280 have you had to recreate the functionality of your eyelids? 0:05:31.640 --> 0:05:34.920 What kind of invention would you have to have to build? 0:05:35.080 --> 0:05:36.680 You've got so many parts of your body that you 0:05:36.760 --> 0:05:39.480 really don't appreciate but would if they were gone, right, 0:05:39.960 --> 0:05:44.760 But enough about Larry McMurtry's cyborg westerns. Uh, let's let's 0:05:44.760 --> 0:05:47.400 just get down to sunglasses. What is essential to a 0:05:47.480 --> 0:05:49.800 modern pair of sunglasses? What do you what do you need? 0:05:49.920 --> 0:05:53.200 Is we're sort of deconstructing the the invention. Well, you 0:05:53.240 --> 0:05:55.760 need a frame to hold them over the eyes, and 0:05:55.880 --> 0:05:58.719 you need lenses that will, in one way or another 0:05:58.880 --> 0:06:02.520 filter the incoming line. They obviously can't be completely okay 0:06:02.520 --> 0:06:04.200 if you need to be able to see through them, 0:06:04.200 --> 0:06:06.960 but they also need to stop some amount of bad 0:06:07.080 --> 0:06:09.960 stuff from getting in right. So, like from from a 0:06:10.320 --> 0:06:14.760 material level, it seems pretty straightforward. Um, you know, glass 0:06:14.839 --> 0:06:17.680 itself is a rather old invention. We could and we 0:06:17.680 --> 0:06:20.240 can really revisit glass at some point in future episode. 0:06:20.240 --> 0:06:23.560 But you find examples of this in ancient Mesopotamia. Uh. 0:06:23.640 --> 0:06:27.839 Certainly crystals and other substances or were known to to 0:06:27.920 --> 0:06:31.880 ancient people. So just the materials of say building something 0:06:31.880 --> 0:06:33.479 out of six, we can all imagine the sort of 0:06:33.480 --> 0:06:38.520 flint stones style uh, spectacles or sunglasses that one could 0:06:38.520 --> 0:06:41.880 conceivably have. But invention is always about that moment where 0:06:41.920 --> 0:06:46.480 someone actually puts materials together and and create something that 0:06:46.640 --> 0:06:49.599 has not existed before. So we're forced to just to 0:06:49.600 --> 0:06:52.080 ask that question, Well, where do we really see the 0:06:52.120 --> 0:06:57.000 earliest indications of uh to all to a certain extent, spectacles. 0:06:57.000 --> 0:06:59.359 We can't talk about sunglasses without talking about spectacles a 0:06:59.360 --> 0:07:03.040 little bit. But we're mostly concerned with sunglasses in this 0:07:03.120 --> 0:07:06.960 episode because they look cooler right focusing lenses. That that's 0:07:06.960 --> 0:07:09.080 the story for another time, where I think we're dealing 0:07:09.160 --> 0:07:12.440 with a somewhat simpler story right now. Yes, even though 0:07:12.480 --> 0:07:15.960 sunglasses might not have become extremely popular around the world 0:07:16.000 --> 0:07:19.120 until after spectacles were widely used. But it's really too 0:07:19.160 --> 0:07:22.920 bad because they're they're they're sunglasses esfecially, there are modern 0:07:23.040 --> 0:07:25.640 usage of them. They're they're they're really important. They really 0:07:25.640 --> 0:07:28.440 protect us. Well, think about the sunglasses you wear as 0:07:28.440 --> 0:07:31.320 a kind of radiation suit for your eyes. I think 0:07:31.320 --> 0:07:33.640 on that one for a second. Try try to actually 0:07:33.720 --> 0:07:37.680 cognize the fact that good old fashioned sunlight is literally 0:07:37.920 --> 0:07:42.000 radiation from a star. That's a phrase that always echoes 0:07:42.040 --> 0:07:44.400 in my mind when it's really beaten down on my head. 0:07:45.040 --> 0:07:47.560 Um and a good pair of sunglasses should do multiple 0:07:47.600 --> 0:07:50.360 things right. They should decrease the intensity of the light 0:07:50.400 --> 0:07:53.040 reaching your eyes. So if it's a bright, shining day, 0:07:53.200 --> 0:07:55.680 or there's glare off of water or off of a 0:07:55.720 --> 0:07:59.240 reflective surface or something. You need light to reach your 0:07:59.240 --> 0:08:01.200 eyes in order to see, but you don't need so 0:08:01.320 --> 0:08:03.400 much of it. And when the number of lumens in 0:08:03.440 --> 0:08:07.000 your surroundings exceed what your eyes need in order to see, 0:08:07.040 --> 0:08:10.400 your iris muscles contract. They shrink your pupil the shutter 0:08:10.440 --> 0:08:13.400 of your eye, and that admits less in. But eventually 0:08:13.520 --> 0:08:16.800 your pupils can't contract anymore, and then you have to 0:08:16.840 --> 0:08:19.240 try to limit more light by squinting your eyelids, but 0:08:19.280 --> 0:08:22.280 eventually you run into problems there. Right, sometimes it's so 0:08:22.360 --> 0:08:25.960 bright that squinting becomes difficult, or you know you you 0:08:25.960 --> 0:08:29.480 you're squinting so much you want to completely close your eyes. Now. 0:08:29.520 --> 0:08:33.200 The other thing that's important for sunglasses to do is 0:08:33.320 --> 0:08:37.600 decrease or eliminate ultra violet radiation when when that's coming 0:08:37.600 --> 0:08:40.800 at your eyes now, there's really no benefit to getting 0:08:40.880 --> 0:08:43.800 ultra violet radiation in your eyes. Whereas you need the 0:08:43.880 --> 0:08:46.480 visible light that comes in from the sun in order 0:08:46.520 --> 0:08:49.440 to see your surroundings, you don't really need UV light 0:08:49.480 --> 0:08:52.880 at all. And so if sunglasses can reduce or even 0:08:52.920 --> 0:08:55.560 completely eliminate U V exposure to your eyes. That's a 0:08:55.559 --> 0:08:57.599 good thing, because your eyes can be injured by u 0:08:57.679 --> 0:09:00.640 V exposure. But as we were saying earlier, also let's 0:09:00.640 --> 0:09:03.240 not ignore the fact that sunglasses are a very profound 0:09:03.360 --> 0:09:06.920 style choice and play a psychological and cultural role as well. 0:09:07.080 --> 0:09:10.760 I think people often wear sunglasses as much for style 0:09:10.920 --> 0:09:14.720 and psychological reasons as they do for uh, for reducing 0:09:14.720 --> 0:09:17.959 glare and reducing UV exposure. In any event, you're gonna 0:09:17.960 --> 0:09:20.600 want a good pair of sunglasses before you go out to, say, 0:09:20.600 --> 0:09:23.560 a sporting event, right for a number of reasons, because 0:09:23.600 --> 0:09:26.920 it's you're you're outdoors and it may be very bright. Uh. 0:09:26.960 --> 0:09:29.559 And then it's also a social engagement. You know, you 0:09:29.840 --> 0:09:33.160 wanna look cool, uh to the other fans or their 0:09:33.400 --> 0:09:35.640 friends and family that have traveled there with you. In 0:09:35.640 --> 0:09:38.000 the case of the dude, you can't go bowling without 0:09:38.000 --> 0:09:43.920 sunglasses exactly. Uh. So, for our first historical journey, in 0:09:44.040 --> 0:09:48.839 our attempt to understand sunglasses of old, let's go back 0:09:49.120 --> 0:09:52.319 to the ancient Romans, Let's go to the Colosseum. Now, 0:09:52.360 --> 0:09:55.120 this I think is actually going to be a false example, 0:09:55.200 --> 0:09:58.000 but it's something that's interesting that sometimes gets cited in 0:09:58.040 --> 0:10:01.079 this context. So we're gonna to our old friend Plenty 0:10:01.080 --> 0:10:03.880 of the Elder first century CE Roman writer in his 0:10:04.000 --> 0:10:08.920 Natural History translated by John Bostock. Plenty is discussing in 0:10:08.920 --> 0:10:11.520 in book thirty seven of his Natural History, quote the 0:10:11.600 --> 0:10:14.640 natural history of precious stones, and he comes to a 0:10:14.679 --> 0:10:19.439 section on what he calls Smaragdes. I could have sworn 0:10:19.600 --> 0:10:22.520 that was one of the one of the raith kings 0:10:22.520 --> 0:10:24.840 in the Lord of the Rings the saga. But I 0:10:24.880 --> 0:10:28.320 don't think so. Which anniversary gift is smar Agnes? I 0:10:28.360 --> 0:10:33.520 can never remember. It's like it's like wood, but ivory Smaragdes. Right, 0:10:34.080 --> 0:10:36.880 So samur agnes appears to be a term used for 0:10:37.000 --> 0:10:40.520 green precious stones, for barrel stones like emerald, or for 0:10:40.640 --> 0:10:43.720 jasper stones. Uh. And he so he seems to be 0:10:43.720 --> 0:10:45.880 talking about emeralds. I think that's the way it's most 0:10:45.920 --> 0:10:48.800 often translated. And Plenty dwells for a while on how 0:10:48.840 --> 0:10:52.079 beautiful the emerald is and how RESTful to the eye, 0:10:52.160 --> 0:10:55.360 how soothing to look upon quote. Even when the vision 0:10:55.400 --> 0:10:58.840 has been fatigued with intently viewing other objects, it is 0:10:58.920 --> 0:11:02.839 refreshed by being turned upon this stone. And lapidaries know 0:11:03.080 --> 0:11:05.920 of nothing that is more gratefully soothing to the eyes. 0:11:06.280 --> 0:11:11.240 It's soft green tints being wonderfully adapted for assuaging lassitude 0:11:11.280 --> 0:11:14.719 when felt in those organs. By those organs, I think 0:11:14.760 --> 0:11:19.280 he means eyes. But anyway, getting to to the part 0:11:19.360 --> 0:11:22.880 that's often cited as as emerald sunglasses, but actually it 0:11:22.920 --> 0:11:25.760 appears to not be, he writes, quote, when the surface 0:11:25.840 --> 0:11:28.760 of the sami agnus is flat, it reflects the image 0:11:28.760 --> 0:11:31.880 of objects in the same manner as a mirror. The 0:11:31.920 --> 0:11:35.439 Emperor Nero used to view the combats of the gladiators 0:11:35.520 --> 0:11:40.760 upon a Smaragdus upon a Smaragdus ban key here perhaps right. 0:11:40.840 --> 0:11:42.920 So this would have been the first century CE, and 0:11:42.960 --> 0:11:46.120 it's been cited as an early use of tinted transparencies 0:11:46.160 --> 0:11:48.800 in the sun. The idea that Nero was maybe watching 0:11:48.840 --> 0:11:53.320 the net fighters and the pursuers the secutors through Gym's 0:11:53.440 --> 0:11:55.800 like lenses. So just I guess try to imagine he's 0:11:55.840 --> 0:11:58.920 holding him rolds over his eyes and looking through them 0:11:58.960 --> 0:12:01.199 like lenses to fill alter out some of the glare. 0:12:01.400 --> 0:12:04.560 I think I also saw an artistic interpretation of this, 0:12:04.600 --> 0:12:08.800 where you see the you know, the the portly emperor, 0:12:08.840 --> 0:12:11.760 they're all in his finery, and he's holding up something 0:12:11.800 --> 0:12:17.040 that looks like it's almost like opera uh binoculars, you know, 0:12:17.080 --> 0:12:19.600 except it's just one emerald that he's holding up to 0:12:19.679 --> 0:12:22.960 his eye. I'm thinking, with the green and that image 0:12:23.000 --> 0:12:25.720 you're describing, this has got to be the inspiration for 0:12:25.800 --> 0:12:29.720 David Lynch's depiction of Baron Harkonen in his adaptation of Dune. 0:12:30.000 --> 0:12:33.240 Oh does he have an emerald? Well, everything's green around. 0:12:33.760 --> 0:12:35.880 It's like his his rooms are green. He's got this 0:12:35.960 --> 0:12:39.240 green environment. He's kind of a Nero like figure. But anyway, 0:12:39.720 --> 0:12:41.520 the reason I said this was a false choice is 0:12:41.559 --> 0:12:44.520 because it sounds to me like in the context Plenty 0:12:44.559 --> 0:12:47.520 meant that Nero if this story is even true. Watched 0:12:47.600 --> 0:12:50.800 the fights as reflected in the surface of the sami 0:12:50.880 --> 0:12:53.760 agnous like a mirror, because he was just talking about 0:12:53.800 --> 0:12:56.320 how it reflects like a mirror, and this would still 0:12:56.360 --> 0:12:59.680 have probably some some like sun dampening effect. Right, just 0:12:59.720 --> 0:13:02.800 tried imagine something reflected an emerald. It's not going to 0:13:02.880 --> 0:13:06.160 be reflected in a blinding way. But so he's looking 0:13:06.200 --> 0:13:09.120 at that since the emerald reflects less light than the 0:13:09.160 --> 0:13:12.400 source provides. I was looking at a text titled the 0:13:12.440 --> 0:13:15.600 Origin and Development of Spectacles by C. J. S. Thompson, 0:13:15.640 --> 0:13:18.040 and this is an older Texas is from N seven, 0:13:18.320 --> 0:13:21.320 but he also mentions the Nero story and he definitely 0:13:21.440 --> 0:13:23.440 argued too that it was probably a case where Nero 0:13:23.600 --> 0:13:28.319 just liked to watch the festivities colored green um which 0:13:28.520 --> 0:13:30.760 you know via the Emerald, and that he gained no 0:13:30.920 --> 0:13:34.479 sun shading from it. And yeah, I think my suspicion 0:13:34.480 --> 0:13:37.480 here is that based on some recent research we did 0:13:37.480 --> 0:13:40.760 for stuff to build your mind about gladiatorial combat for 0:13:40.800 --> 0:13:44.000 our episode on the trident Um, you know there there 0:13:44.080 --> 0:13:47.400 was if you're a fan of both the sort of 0:13:47.440 --> 0:13:52.960 the sporting combat of of the gladiatorial spectacle as well 0:13:53.000 --> 0:13:56.199 as like the drama and all these other ridiculous aspects 0:13:56.280 --> 0:13:59.120 of it, you're gonna be you might you might gain 0:13:59.240 --> 0:14:02.480 something from looking out at this combat between men dressed 0:14:02.520 --> 0:14:06.280 as fish men using nautical weapons and then adding a 0:14:06.320 --> 0:14:10.440 green overlay on that. UM. I could see where where 0:14:10.440 --> 0:14:14.040 the green tent could perhaps be be helpful in that 0:14:14.480 --> 0:14:17.120 that particular mode of entertainment. What you're saying is taking 0:14:17.120 --> 0:14:20.960 on a decidedly Lynchian vibe. I I think I think 0:14:20.960 --> 0:14:24.840 the connection is there now Thompson also points out that 0:14:24.840 --> 0:14:28.280 while the Romans certainly suffered from eye problems and had 0:14:28.280 --> 0:14:31.520 their own treatments for those ailments, there's no mention in 0:14:31.520 --> 0:14:36.080 the work of say Celsus of artificial site aids. He 0:14:36.120 --> 0:14:39.520 mentions that in writings prior to the thirteenth century, one 0:14:39.640 --> 0:14:43.480 finds only occasional mentions of magnifying classes. So the use 0:14:43.520 --> 0:14:46.320 of some sort of a lens to uh look at 0:14:46.360 --> 0:14:49.000 finder details or perhaps you know, holding it up to 0:14:49.360 --> 0:14:53.000 a text. But uh, you don't see mention of spectacles, 0:14:53.720 --> 0:14:55.240 by the way. He also wrote that there was no 0:14:55.360 --> 0:14:58.320 evidence that lenses were known to the ancient Egyptians or 0:14:58.360 --> 0:15:03.080 the Hebrews. However, we do have a very early magnifying glass, 0:15:03.360 --> 0:15:06.640 or depending on who you ask, perhaps a fire starting glass, 0:15:06.680 --> 0:15:09.160 something that you used to refract the rays of the sun, 0:15:09.240 --> 0:15:11.680 you know, to start a small fire. Uh, you know, 0:15:11.720 --> 0:15:15.200 the kind of thing that children may sometimes do when 0:15:15.240 --> 0:15:18.280 trying to burn ants, hopefully not to ants, hopefully not. 0:15:18.360 --> 0:15:21.320 I mean, and you know one has to be careful, 0:15:21.720 --> 0:15:25.680 but at any rate, this particular lens, the Nimrod lens, 0:15:26.160 --> 0:15:28.880 is a three thousand year old crystal unearthed in eighteen 0:15:28.920 --> 0:15:34.760 fifty by Austin Henry layered in the Syrian Palace of Nimrod. However, 0:15:35.560 --> 0:15:37.320 we were also not sure. It might have simply been 0:15:37.360 --> 0:15:40.960 a decorative element. It might not have been used. Uh. 0:15:40.960 --> 0:15:43.360 And in any rate, it's not tinted. Okay, so we're 0:15:43.360 --> 0:15:45.600 not talking about sunglasses, right, but we are talking about 0:15:45.600 --> 0:15:48.280 like a crystal that may have been that people may 0:15:48.320 --> 0:15:50.640 have looked through. And now you have to ask you 0:15:51.080 --> 0:15:53.120 the question, like to what extent did they just look 0:15:53.200 --> 0:15:55.840 through it because it was cool? Like what's more mystical 0:15:56.200 --> 0:15:59.920 than holding up some sort of you know, gleaming crystal, 0:16:00.040 --> 0:16:03.400 even if it's clear, and watching how the world is 0:16:03.440 --> 0:16:07.000 distorted ever so slightly. Now, another thing that's worth noting 0:16:07.200 --> 0:16:10.120 is that we've been talking about lenses and tinted lenses. 0:16:10.160 --> 0:16:13.760 But obviously people came up with ways of protecting their 0:16:13.800 --> 0:16:17.640 eyes from the sun, uh, having accessories beyond just their 0:16:17.640 --> 0:16:20.280 hands and their eyelids and stuff to protect their eyes 0:16:20.360 --> 0:16:24.040 from the sun long before there were there were tinted 0:16:24.080 --> 0:16:29.119 glass or plastic lenses or anything, for example, hats and umbrellas. 0:16:29.240 --> 0:16:32.880 That's obvious, yeah, But a much more ingenious and much 0:16:32.920 --> 0:16:36.080 more interesting one is what I want to mention the Inuit, 0:16:36.160 --> 0:16:40.680 and you pick people's of the northern circumpolar regions today Canada, Alaska, 0:16:40.760 --> 0:16:45.119 Greenland and Russia have for centuries made these ingenious devices 0:16:45.200 --> 0:16:48.560 known as snow goggles. Yes, and and I want to 0:16:48.560 --> 0:16:50.840 come back to what we said earlier about lumens before 0:16:50.840 --> 0:16:52.880 we get into this, because I think this really drives 0:16:52.920 --> 0:16:56.800 home the necessity that led to the invention. Uh. So, 0:16:57.560 --> 0:17:00.800 in an indoor environment, a humanist typically typically going to 0:17:00.880 --> 0:17:04.359 encounter four hundred, six hundred lumens. That's the intensity of 0:17:04.400 --> 0:17:08.320 the light um and our comfortable level four loomens, it's's 0:17:08.320 --> 0:17:11.800 gonna go up to round thirty five hundred. If you're 0:17:11.800 --> 0:17:14.600 in the shade on a sunny day, you're probably encountering 0:17:14.640 --> 0:17:17.520 around a thousand lumens sunny day out on say a 0:17:17.640 --> 0:17:20.199 highway or other reflective surface. You know, we all know 0:17:20.240 --> 0:17:22.040 what it's like to drive on like a really sunny day. 0:17:22.040 --> 0:17:24.760 You almost have to have shades. Uh, you're probably gonna 0:17:24.760 --> 0:17:28.080 do with something like six thousand or more lumens. Uh. 0:17:28.119 --> 0:17:30.760 Ten thousand lumens is the danger zone where you really 0:17:30.760 --> 0:17:32.879 have to start worrying about the health of your eyes. 0:17:33.560 --> 0:17:36.320 But a snow field on a sunny day, you're talking 0:17:37.119 --> 0:17:40.400 twelve thousand plus lumens. And this is where you enter 0:17:40.440 --> 0:17:43.680 the domain of potential snow blindness. Right and this is 0:17:43.720 --> 0:17:47.119 of course because of the reflective power of white snow. Right. Uh, 0:17:47.400 --> 0:17:50.120 you can create almost kind of double sun effects, sun 0:17:50.160 --> 0:17:53.840 above and sun below being reflected back up. Whereas you know, 0:17:54.200 --> 0:17:57.199 a normal patch of ground that's got say grass or 0:17:57.280 --> 0:18:00.560 just open soil, might reflect about ten percent of the 0:18:00.680 --> 0:18:03.480 UV ray is coming from the sun. Snow can reflect 0:18:03.560 --> 0:18:05.919 not quite a hundred percent, but something like close to 0:18:05.960 --> 0:18:10.000 a of it, nearly doubling your UV exposure. And so 0:18:10.160 --> 0:18:12.800 if you are, say living in in northern regions where 0:18:12.800 --> 0:18:15.440 there's a lot of snow cover, one thing that works 0:18:15.440 --> 0:18:17.240 in your favor is that for much of the year, 0:18:17.400 --> 0:18:20.199 the sun doesn't get super bright, right, it doesn't get 0:18:20.240 --> 0:18:22.840 super high in the sky, doesn't get super direct, but 0:18:23.119 --> 0:18:25.080 it will in certain parts of the year where there 0:18:25.200 --> 0:18:27.080 is still a lot of snow cover on the ground. 0:18:27.119 --> 0:18:30.359 So when you've got those things working together, say bright sun, 0:18:30.960 --> 0:18:33.800 heavy snow cover, maybe in the springtime when the sun 0:18:33.880 --> 0:18:36.480 is out high in the sky, proper eye protection is 0:18:36.520 --> 0:18:39.840 incredibly important, and not just because it's difficult to hunt 0:18:39.920 --> 0:18:42.680 or see where you're going when the sun's reflecting off 0:18:42.680 --> 0:18:45.040 the white snow and there's blinding glare and everything. But 0:18:45.080 --> 0:18:48.000 it's what you mentioned, there's this risk of snow blindness, 0:18:48.240 --> 0:18:51.679 which is also known as a photocrotitis. So, as we 0:18:51.760 --> 0:18:55.119 mentioned earlier, part of natural sunlight is ultra violet radiation, 0:18:55.200 --> 0:18:58.480 and ultra violet radiation can damage the cornea. It can 0:18:58.560 --> 0:19:01.439 damage the conjunctiva, the outer surfaces of the eye, just 0:19:01.520 --> 0:19:04.040 like it can damage the skin. And this is why 0:19:04.080 --> 0:19:07.439 photocharrotitis is often described as something like quote sunburn of 0:19:07.520 --> 0:19:11.080 the eye. Symptoms include pain and feeling of having like 0:19:11.200 --> 0:19:15.160 irritans or foreign bodies lodged in the eye, tearing up, 0:19:15.280 --> 0:19:19.960 swelling and redness, light sensitivity, and sometimes even truly temporary 0:19:20.080 --> 0:19:23.320 loss of vision. That's where the blindness comes from. And 0:19:23.400 --> 0:19:25.639 so if you need to be doing stuff out in 0:19:25.720 --> 0:19:28.040 the snow where the sun is bright, this this is 0:19:28.080 --> 0:19:30.240 going to be a problem. And snow goggles fight this 0:19:30.280 --> 0:19:34.560 problem with a very smart design. They're typically a carved frame, 0:19:34.880 --> 0:19:39.440 usually made from animal bone or walrus tusks, sometimes from driftwood, 0:19:39.880 --> 0:19:43.360 or sometimes even from like strange materials like I saw 0:19:43.400 --> 0:19:45.640 one that I think was from baleen from a whale. 0:19:46.440 --> 0:19:49.639 And uh, this frame fits tight over the eyes so 0:19:49.720 --> 0:19:51.960 that light doesn't get in on the sides or the top, 0:19:52.240 --> 0:19:55.920 and then light is allowed to enter through two very wide, 0:19:56.119 --> 0:19:59.879 very narrow slots carved in the middle of the goggles, 0:20:00.080 --> 0:20:03.080 which are sometimes darkened on the inside with a material 0:20:03.200 --> 0:20:07.040 like soot. And these narrow slits allow the person wearing 0:20:07.080 --> 0:20:09.600 them to see without exposing their eyes to too much 0:20:09.640 --> 0:20:13.680 glare or UV radiation. And some alternate versions also have 0:20:13.680 --> 0:20:17.560 have multiple slits more like like shutter shades or Venetian 0:20:17.600 --> 0:20:21.080 blinds or something. They're not unlike the sort of novelty 0:20:21.240 --> 0:20:24.960 plastic nineteen eighties sunglasses you know where there where you 0:20:25.040 --> 0:20:28.280 just had you had no glass, no lens, shutters, these slits, yes, 0:20:28.320 --> 0:20:31.959 so shutter shapes, which yeah, you look at the especially 0:20:32.000 --> 0:20:34.359 the nineteen eighties versions of these, and it's easy to 0:20:34.440 --> 0:20:37.240 just think, this is ridiculous. This is the this is 0:20:37.280 --> 0:20:41.760 the sunglasses, this is eye wear. Is a purely decorative element, 0:20:41.960 --> 0:20:43.679 and to a certain extent is true. But they do 0:20:43.720 --> 0:20:46.040 have a certain functionality as well. Yeah, and in many 0:20:46.080 --> 0:20:49.600 ways a highly effective functionality. I mean this, if you 0:20:49.680 --> 0:20:52.080 don't have tinted glass to work with. This is a 0:20:52.160 --> 0:20:55.960 genius design. Yeah, and and the necessity that led to 0:20:56.000 --> 0:20:58.480 it like like this would this would be the kind 0:20:58.480 --> 0:21:03.040 of environment that would necessitate sunglasses, UM in a way 0:21:03.119 --> 0:21:05.879 that other parts of the world did not. All right, Well, 0:21:05.880 --> 0:21:07.879 on that note, let's take a quick break, and when 0:21:07.880 --> 0:21:11.280 we come back, we'll discuss some more curios from the 0:21:11.480 --> 0:21:16.360 UH the history of invention UH in regards to the sunglasses. 0:21:21.800 --> 0:21:26.240 All right, we're back now. Another frequently sided example of 0:21:26.240 --> 0:21:30.080 of sunglasses or early sunglasses used UH involved them not 0:21:30.119 --> 0:21:33.159 being used to protect against the sun or perhaps in 0:21:33.200 --> 0:21:37.280 any way affect vision, but that they were allegedly used 0:21:37.640 --> 0:21:41.040 just to hide your eyes from others. This is this 0:21:41.160 --> 0:21:44.720 is a crucially important part of sunglasses. Could not ignore it. 0:21:44.840 --> 0:21:47.400 I mean, think of all the times you've worn sunglasses. 0:21:47.440 --> 0:21:49.560 And there are times where you wear them to protect 0:21:49.640 --> 0:21:53.240 your eyes. There are times when you wear them to 0:21:53.240 --> 0:21:56.640 to see better than high a light intensive environment. There 0:21:56.640 --> 0:21:59.200 are times when you do it to look cool. But 0:21:59.280 --> 0:22:02.000 there are times when say I've I've warned them, for instance, 0:22:02.080 --> 0:22:06.680 on the train before UH, even when the train is underground, 0:22:07.240 --> 0:22:09.879 because it kind of makes me a little invisible if 0:22:09.920 --> 0:22:13.360