WEBVTT - Invention Playlist 4: Sun Glasses 0:00:08.840 --> 0:00:12.400 Hey, welcome to Invention. My name is Robert Lamb and 0:00:12.440 --> 0:00:16.400 I'm Joe McCormick. Robert, what kind of sunglasses do you wear? Well? Currently, 0:00:17.120 --> 0:00:19.640 my son is six years old, so I've been going 0:00:19.640 --> 0:00:22.640 through a spell here where I can really only wear 0:00:23.200 --> 0:00:27.360 whatever kind of semi garbage swag sunglasses come my way, 0:00:27.400 --> 0:00:30.240 you know, with various brand names plastered to the side 0:00:30.280 --> 0:00:33.720 of them, because inevitably, especially when he was younger, my 0:00:33.800 --> 0:00:36.919 son would have to get his hands on whatever kind 0:00:36.920 --> 0:00:39.640 of sunglasses I had in the car. So the sunglasses 0:00:39.680 --> 0:00:44.839 get smudged, sunglasses get scratched up, sunglasses get broken or 0:00:45.000 --> 0:00:47.800 just lost. And I was pretty good at losing sunglasses 0:00:47.880 --> 0:00:50.880 even before he came into my life. Uh So I'm 0:00:51.120 --> 0:00:53.920 hoping that I'm working up to very soon reaching that 0:00:54.040 --> 0:00:57.200 point where I can actually buy a decent pair of 0:00:57.240 --> 0:01:00.000 sunglasses that will protect my eyes. Did you ever actually 0:01:00.120 --> 0:01:05.480 where those company sunglasses we got, I have like like 0:01:05.520 --> 0:01:08.920 fold in half at the nose. Yeah, I got those immediately. 0:01:09.080 --> 0:01:11.280 But mainly I I thought to myself, this is a 0:01:11.280 --> 0:01:14.000 great decoy brand because my son is gonna love like 0:01:14.040 --> 0:01:18.320 the Transformer s qualities of these sunglasses here. Break that one. Yeah, 0:01:18.480 --> 0:01:21.160 but I've ended up wearing them around anyway, So that's 0:01:21.200 --> 0:01:23.600 my story. Hopefully, by the time I'm ready to actually 0:01:23.640 --> 0:01:26.560 get some decent sunglasses, we'll have some like back to 0:01:26.600 --> 0:01:29.240 the future to sunglasses, you know, like the ones that 0:01:29.280 --> 0:01:32.280 you've got as a prize, uh Pizza Hut back in 0:01:32.319 --> 0:01:34.480 the day when that film first came out. Except now 0:01:34.520 --> 0:01:37.399 these will be legit future sunglasses. You know. I was 0:01:37.440 --> 0:01:39.960 trying to think before we decided to do this episode, 0:01:39.959 --> 0:01:43.760 our sunglasses an invention or not? Did they count? Yeah? 0:01:43.800 --> 0:01:46.800 They count? I guess everything is an invention. Were we 0:01:46.880 --> 0:01:50.240 born with sunglasses? Well we'll get into that, but yeah, 0:01:50.240 --> 0:01:53.720 it is difficult for us to imagine a time before sunglasses. 0:01:54.080 --> 0:01:56.560 How did Corey Hart keep track of the visions in 0:01:56.600 --> 0:01:59.400 his eyes? I don't know. How did rowdy Roddy Piper 0:01:59.480 --> 0:02:03.080 see through the alien conspiracy? I guess I don't know. 0:02:03.160 --> 0:02:05.760 He didn't how to terminate or cover up his eye damage. 0:02:06.360 --> 0:02:08.800 That's a good point, bro, Really, how did anyone ever 0:02:09.360 --> 0:02:11.720 in the history of Earth managed to look cool at 0:02:11.760 --> 0:02:14.360 any given moment, much less shade their eyes from the 0:02:14.480 --> 0:02:16.960 vicious light of day. It's already telling that all the 0:02:17.000 --> 0:02:20.000 examples you point to our cultural ones you're pointing, You're 0:02:20.000 --> 0:02:22.720 pointing to movies and stuff rather than talking about how 0:02:22.760 --> 0:02:25.920 would I get through my life without sunglasses? Well, that 0:02:26.280 --> 0:02:27.679 this is going to be an important part there, just 0:02:27.919 --> 0:02:30.560 the iconography of the sunglasses, and that will be more 0:02:30.600 --> 0:02:33.320 important later on in our discussion, but in their their 0:02:33.320 --> 0:02:38.200 psychological effects example that. But initially here you know, we're 0:02:38.240 --> 0:02:41.600 we're we're complicating the purpose of the sunglasses. Bye bye. Basically, 0:02:42.480 --> 0:02:45.000 the whole deal is the sun is bright. I disagree. 0:02:45.880 --> 0:02:48.400 And while our eyelids do give us the ability to 0:02:48.440 --> 0:02:51.840 manipulate the amount of sunlight hitting our eyeballs, it also 0:02:51.919 --> 0:02:54.920 pays to have other options. And certainly we have the 0:02:54.960 --> 0:02:57.160 ability to look away from the sun, to hide from 0:02:57.160 --> 0:03:00.720 the sun, or to raise a hand or forearm to 0:03:00.800 --> 0:03:05.280 block it. But that's dependent largely on say, your environment. 0:03:05.520 --> 0:03:08.480 Like some environments are much brighter than others. What if 0:03:08.520 --> 0:03:11.320 you live in a place where, say it's springtime and 0:03:11.360 --> 0:03:14.919 you're in a place with snow cover. The sun can 0:03:14.960 --> 0:03:17.399 be so bright in those cases because it's not only 0:03:17.440 --> 0:03:20.200 coming from above but reflecting off of the snow, that 0:03:20.280 --> 0:03:24.359 you essentially cannot use your eyes in the environment, right 0:03:24.360 --> 0:03:27.000 because otherwise you can't just shade where a hat you 0:03:27.040 --> 0:03:28.840 need to wear like a hat with two bills right, 0:03:28.919 --> 0:03:31.560 one on top, one at the bottom. Um, it's coming 0:03:31.560 --> 0:03:33.560 from all directions, and you need to use your hands 0:03:33.560 --> 0:03:36.640 for other things. You're an individual, will need to to 0:03:36.720 --> 0:03:39.840 hunt or fish or craft, etcetera. You can't just go 0:03:39.880 --> 0:03:43.960 around with your hands up all the time. Um. When 0:03:44.000 --> 0:03:48.280 I when I think about the challenges of dealing with sunlight, 0:03:48.920 --> 0:03:51.440 I'm always forced to just think about how amazing our 0:03:51.440 --> 0:03:55.800 eyelids are though for manipulating light well, and our iris is. 0:03:55.880 --> 0:03:58.640 Of course, our pupils contract when there's too much light, 0:03:58.680 --> 0:04:00.960 but there's a point at which they can't contract anymore, 0:04:01.000 --> 0:04:04.080 and you have to depend on the eyelids. One of 0:04:04.200 --> 0:04:06.280 one example I always go to is there's a character 0:04:06.440 --> 0:04:11.000 in Larry McMurtry's novel Comanche Moon and he he winds 0:04:11.120 --> 0:04:18.400 up tortured by bandit flares and they slice his eyelids off. 0:04:19.120 --> 0:04:21.800 They leave him for for dead in the sun, and he's, 0:04:21.880 --> 0:04:23.960 you know, half driven mad by the whole whole ordeal. 0:04:24.200 --> 0:04:27.280 But eyelids. Oh yeah. It is a It is a sick, 0:04:27.320 --> 0:04:31.240 weird book. Um, I love it. It's my favorite McMurtry book. 0:04:31.640 --> 0:04:35.560 But afterwards this character ends up constructing a pair of 0:04:35.600 --> 0:04:42.120 special sunglasses for himself with these varying um varying levels 0:04:42.120 --> 0:04:44.760 of darkness, so that he can just click through them 0:04:44.760 --> 0:04:46.800 as he needs them, depending on where he is, if 0:04:46.839 --> 0:04:50.839 he's a you know, indoors, outdoors, bright day, uh, you know, 0:04:51.240 --> 0:04:54.320 cloudy day, etcetera. But I always come back to that 0:04:54.320 --> 0:04:56.279 because it's like, Yeah, have you had to recreate the 0:04:56.320 --> 0:04:59.800 functionality of your eyelids? What kind of invention would you 0:04:59.839 --> 0:05:02.640 have to have to build? You've got so many parts 0:05:02.680 --> 0:05:04.960 of your body that you really don't appreciate but would 0:05:04.960 --> 0:05:10.680 if they were gone. But enough about Larry merturs cyborg westerns. Uh, 0:05:10.960 --> 0:05:13.160 let's let's just get down to sunglasses. Was what is 0:05:13.279 --> 0:05:15.880 essential to a modern pair of sunglasses? What do you 0:05:15.920 --> 0:05:18.359 What do you need is we're sort of deconstructing the 0:05:18.360 --> 0:05:21.280 the invention. Well, you need a frame to hold them 0:05:21.279 --> 0:05:24.400 over the eyes, and you need lenses that will, in 0:05:24.480 --> 0:05:27.800 one way or another filter the incoming light. They obviously 0:05:27.839 --> 0:05:30.160 can't be completely opaque. You need to be able to 0:05:30.200 --> 0:05:32.640 see through them, but they also need to stop some 0:05:32.760 --> 0:05:36.160 amount of bad stuff from getting in right, So, like 0:05:36.200 --> 0:05:40.400 from from a material level, it seems pretty straightforward. Um. 0:05:40.720 --> 0:05:43.719 You know, glass itself is a rather old invention. We 0:05:43.760 --> 0:05:46.040 could and we can revisit glass at some point in 0:05:46.040 --> 0:05:48.520 a future episode. But you find examples of this an 0:05:48.520 --> 0:05:54.080 ancient Mesopotamia. Uh. Certainly crystals and other substances were known 0:05:54.120 --> 0:05:58.279 to ancient people. So just the materials of say, building 0:05:58.279 --> 0:06:00.120 something out of six, we can all imagine this of 0:06:00.160 --> 0:06:05.159 flint stones style UH, spectacles or sunglasses that one could 0:06:05.200 --> 0:06:08.560 conceivably have. But invention is always about that moment where 0:06:08.560 --> 0:06:13.160 someone actually puts materials together and and create something that 0:06:13.320 --> 0:06:16.240 has not existed before. So we're forced to just to 0:06:16.279 --> 0:06:18.719 ask that question, well, where do we really see the 0:06:18.800 --> 0:06:23.680 earliest indications of UH to all to a certain extent, spectacles, 0:06:23.680 --> 0:06:25.960 We can't talk about sunglasses without talking about spectacles a 0:06:26.040 --> 0:06:29.720 little bit. But we're mostly concerned with sunglasses in this 0:06:29.800 --> 0:06:33.600 episode because they look cooler right focusing lenses. That that's 0:06:33.600 --> 0:06:35.799 the story for another time, where I think we're dealing 0:06:35.800 --> 0:06:39.120 with a somewhat simpler story right now. Yes, even though 0:06:39.160 --> 0:06:42.600 sunglasses might not have become extremely popular around the world 0:06:42.680 --> 0:06:45.840 until after spectacles were widely used. But it's really too 0:06:45.839 --> 0:06:50.000 bad because they're they're they're sunglasses esfecially are modern usage 0:06:50.000 --> 0:06:53.000 of them. They're they're they're really important, they really protect us. Well, 0:06:53.040 --> 0:06:55.480 think about the sunglasses you wear as a kind of 0:06:55.560 --> 0:06:58.440 radiation suit for your eyes. I think on that one 0:06:58.480 --> 0:07:01.159 for a second. Try try to act, actually cognize the 0:07:01.240 --> 0:07:05.599 fact that good old fashioned sunlight is literally radiation from 0:07:05.600 --> 0:07:08.919 a star. That's a phrase that always echoes in my 0:07:08.960 --> 0:07:12.000 mind when it's really beaten down on my head um. 0:07:12.040 --> 0:07:14.720 And a good pair of sunglasses should do multiple things, right. 0:07:14.760 --> 0:07:17.800 They should decrease the intensity of the light reaching your eyes. 0:07:17.800 --> 0:07:20.760 So if it's a bright, shining day, or there's glare 0:07:20.840 --> 0:07:23.760 off of water or off of a reflective surface or something, 0:07:24.320 --> 0:07:26.920 you need light to reach your eyes in order to see, 0:07:26.960 --> 0:07:28.720 but you don't need so much of it. And when 0:07:28.760 --> 0:07:32.280 the number of lumens in your surroundings exceed what your 0:07:32.320 --> 0:07:35.120 eyes need in order to see, your iris muscles contract. 0:07:35.280 --> 0:07:37.880 They shrink your pupil, the shutter of your eye, and 0:07:38.000 --> 0:07:42.240 that admits less in But eventually your pupils can't contract anymore, 0:07:42.760 --> 0:07:44.600 and then you have to try to limit more light 0:07:44.600 --> 0:07:48.160 by squinting your eyelids. But eventually you run into problems there. Right, 0:07:48.200 --> 0:07:52.080 sometimes it's so bright that squinting becomes difficult, or you know, 0:07:52.160 --> 0:07:54.640 you you you're squinting so much you want to completely 0:07:54.680 --> 0:07:58.120 close your eyes. Now, the other thing that's important for 0:07:58.360 --> 0:08:02.800 sunglasses to do is decrease or eliminate ultra violet radiation 0:08:03.000 --> 0:08:05.640 when when that's coming at your eyes. Now, there's really 0:08:05.680 --> 0:08:09.440 no benefit to getting ultra violet radiation in your eyes. 0:08:09.520 --> 0:08:12.120 Whereas you need the visible light that comes in from 0:08:12.160 --> 0:08:14.760 the sun in order to see your surroundings, you don't 0:08:14.800 --> 0:08:17.960 really need UV light at all. And so if sunglasses 0:08:18.000 --> 0:08:21.960 can reduce or even completely eliminate UV exposure to your eyes, 0:08:22.000 --> 0:08:23.960 that's a good thing, because your eyes can be injured 0:08:24.000 --> 0:08:26.560 by U V exposure. But as we were saying earlier, 0:08:26.680 --> 0:08:29.040 also let's not ignore the fact that sunglasses are a 0:08:29.160 --> 0:08:32.800 very profound style choice and play a psychological and cultural 0:08:32.920 --> 0:08:36.160 role as well. I think people often wear sunglasses as 0:08:36.360 --> 0:08:40.600 much for style and psychological reasons as they do for uh, 0:08:40.679 --> 0:08:44.120 for reducing glare and reducing UV exposure. In any event, 0:08:44.200 --> 0:08:46.800 you're gonna want a good pair of sunglasses before you 0:08:46.800 --> 0:08:49.240 go out to say a sporting event, right for a 0:08:49.320 --> 0:08:51.880 number of reasons, because it's your your outdoors, and it 0:08:52.000 --> 0:08:54.760 may be very bright. Uh. And then it's also a 0:08:54.840 --> 0:08:58.600 social engagement. You know, you wanna look cool uh to 0:08:58.720 --> 0:09:01.200 the other fans or they're friends and family that have 0:09:01.240 --> 0:09:03.199 traveled there with you. In the case of the dude, 0:09:03.240 --> 0:09:07.880 you can't go bowling without sunglasses exactly. Uh. So for 0:09:07.920 --> 0:09:13.479 our first historical journey, in our attempt to understand sunglasses 0:09:13.520 --> 0:09:17.200 of old, let's go back to the ancient Romans. Let's 0:09:17.240 --> 0:09:20.120 go to the Colosseum. Now, this, I think is actually 0:09:20.120 --> 0:09:22.760 going to be a false example, but it's something that's 0:09:22.800 --> 0:09:26.360 interesting that sometimes gets cited in this context. So we're 0:09:26.360 --> 0:09:28.240 gonna go to our old friend Plenty of the Elder 0:09:28.440 --> 0:09:32.479 first century CE Roman writer in his Natural History translated 0:09:32.480 --> 0:09:36.440 by John Bostock, Plenty is discussing in in book thirty 0:09:36.440 --> 0:09:39.120 seven of his Natural History quote the natural history of 0:09:39.160 --> 0:09:42.000 precious Stones, and he comes to a section on what 0:09:42.120 --> 0:09:46.960 he calls smaragdes I could have sworn that was one 0:09:47.000 --> 0:09:49.640 of the one of the raith kings in the Lord 0:09:49.679 --> 0:09:52.240 of the Rings uh saga. But I don't think so. 0:09:52.440 --> 0:09:55.840 Which anniversary gift is smar agnes I can never remember? 0:09:55.880 --> 0:10:00.840 It's like it's like wood, but ivory smaragdes right. So 0:10:01.000 --> 0:10:03.959 samur agnes appears to be a term used for green 0:10:04.120 --> 0:10:08.200 precious stones, for barrel stones like emerald, or for jasper stones. 0:10:08.800 --> 0:10:11.440 Uh and he so he seems to be talking about emeralds. 0:10:11.480 --> 0:10:13.880 I think that's the way it's most often translated. And 0:10:13.880 --> 0:10:16.760 plenty dwells for a while on how beautiful the emerald 0:10:16.840 --> 0:10:19.640 is and how RESTful to the eye, how soothing to 0:10:19.679 --> 0:10:22.959 look upon. Quote, even when the vision has been fatigued 0:10:23.040 --> 0:10:26.760 with intently viewing other objects, it is refreshed by being 0:10:26.760 --> 0:10:30.440 turned upon this stone. And lapidaries know of nothing that 0:10:30.600 --> 0:10:33.880 is more gratefully soothing to the eyes. It's soft green 0:10:33.920 --> 0:10:38.800 tints being wonderfully adapted for assuaging lassitude when felt in 0:10:38.840 --> 0:10:42.880 those organs, by those organs, I think he means eyes. 0:10:43.960 --> 0:10:46.920 But anyway, getting to to the part that's often cited 0:10:46.960 --> 0:10:50.440 as as emerald sunglasses, but actually it appears to not be, 0:10:50.760 --> 0:10:53.480 he writes. Quote. When the surface of the samur agnes 0:10:53.600 --> 0:10:56.400 is flat, it reflects the image of objects in the 0:10:56.440 --> 0:10:59.839 same manner as a mirror. The Emperor Nero used to 0:11:00.040 --> 0:11:04.559 you the combats of the gladiators upon a Smaragdus upon 0:11:04.920 --> 0:11:08.200 a Smaragdus being key here perhaps right. So this would 0:11:08.200 --> 0:11:10.400 have been the first century CE, and it's been cited 0:11:10.440 --> 0:11:13.360 as an early use of tinted transparencies in the sun. 0:11:13.440 --> 0:11:16.479 The idea that Nero was maybe watching the net fighters 0:11:16.520 --> 0:11:20.800 and the pursuers the secutors through Gym's like lenses. So 0:11:20.880 --> 0:11:23.680 just I guess try to imagine he's holding emeralds over 0:11:23.720 --> 0:11:26.800 his eyes and looking through them like lenses to filter 0:11:26.880 --> 0:11:29.080 out some of the glare. I think I also saw 0:11:29.200 --> 0:11:32.520 an artistic interpretation of this where you see the you know, 0:11:32.640 --> 0:11:37.480 the the portly emperor. They're all in his finery and 0:11:37.480 --> 0:11:39.920 he's holding up something that looks like it's almost like 0:11:40.840 --> 0:11:45.280 opera uh, binoculars, you know, except it's just one emerald 0:11:45.320 --> 0:11:47.800 that he's holding up to his eye. I'm thinking with 0:11:47.840 --> 0:11:51.200 the green and that image you're describing, this has got 0:11:51.200 --> 0:11:54.120 to be the inspiration for David Lynch's depiction of Baron 0:11:54.160 --> 0:11:57.280 Harconan in his adaptation of Dune. Oh does he have 0:11:57.320 --> 0:12:01.280 an emerald? Well, everything's green around. It's like his his 0:12:01.400 --> 0:12:03.840 rooms are green. He's got this green environment. He's kind 0:12:03.840 --> 0:12:06.839 of a Nero like figure. But anyway, the reason I 0:12:06.880 --> 0:12:09.120 said this was a false choices because it sounds to 0:12:09.200 --> 0:12:12.320 me like in the context, Plenty meant that Nero, if 0:12:12.320 --> 0:12:16.000 this story is even true, watched the fights as reflected 0:12:16.080 --> 0:12:18.840 in the surface of the sami Agnodus like a mirror, 0:12:19.280 --> 0:12:21.320 because he was just talking about how it reflects like 0:12:21.320 --> 0:12:24.280 a mirror, and this would still have probably some some 0:12:24.480 --> 0:12:27.200 like sun dampening effect, right. I just try to imagine 0:12:27.200 --> 0:12:30.160 something reflected an emerald. It's not going to be reflected 0:12:30.160 --> 0:12:33.120 in a blinding way, but so he's looking at that 0:12:33.160 --> 0:12:36.720 since the emerald reflects less light than the source provides. 0:12:37.120 --> 0:12:39.600 I was looking at a text titled The Origin and 0:12:39.640 --> 0:12:42.520 Development of Spectacles by C. J. S. Thompson, and this 0:12:42.559 --> 0:12:45.200 is an older Texas Is from n seven, but he 0:12:45.240 --> 0:12:48.600 also mentions the Nero story, and he definitely argued too 0:12:48.640 --> 0:12:50.800 that it was probably a case where Nero just liked 0:12:50.880 --> 0:12:55.320 to watch the festivities colored green um which you know 0:12:55.440 --> 0:12:58.320 via the emerald, and that he gained no sun shading 0:12:58.440 --> 0:13:01.480 from it. And yeah, I think my suspicion here is 0:13:01.520 --> 0:13:04.480 that based on some recent research we did for stuff 0:13:04.520 --> 0:13:07.600 to build your mind about gladiatorial combat was for our 0:13:07.679 --> 0:13:10.840 episode on the trident Um, you know there there was. 0:13:11.080 --> 0:13:14.160 If you're a fan of both the sort of the 0:13:14.760 --> 0:13:19.840 sporting combat of of the gladiatorial spectacle as well as 0:13:19.880 --> 0:13:23.240 like the drama and all these other ridiculous aspects of it, 0:13:23.640 --> 0:13:26.480 you're gonna be you might you might gain something from 0:13:26.679 --> 0:13:29.680 looking out at this combat between men dressed as fish 0:13:30.080 --> 0:13:33.920 men using nautical weapons, and then adding a green overlay 0:13:34.040 --> 0:13:37.600 on that. Um, I could see where where the green 0:13:37.679 --> 0:13:41.800 tint could perhaps be be helpful in that that particular 0:13:41.920 --> 0:13:44.440 mode of entertainment. What you're saying is taking on a 0:13:44.520 --> 0:13:48.200 decidedly Lynchian vibe. I I think, I think the connection 0:13:48.280 --> 0:13:51.800 is there now. Thompson also points out that while the 0:13:51.920 --> 0:13:55.280 Romans certainly suffered from eye problems and had their own 0:13:55.320 --> 0:13:58.520 treatments for those ailments, there's no mention in the work 0:13:58.559 --> 0:14:03.240 of say Celsus, of artificial site aids. He mentions that 0:14:03.280 --> 0:14:06.959 in writings prior to the thirteenth century, one finds only 0:14:07.000 --> 0:14:10.400 occasional mentions of magnifying classes. So the use of some 0:14:10.480 --> 0:14:13.320 sort of a lens to uh look at find our 0:14:13.400 --> 0:14:16.560 details or perhaps you know, holding it up to a text, 0:14:16.880 --> 0:14:20.800 but uh, you don't see mention of spectacles. By the way, 0:14:20.800 --> 0:14:23.160 he also wrote that there was no evidence that lenses 0:14:23.200 --> 0:14:26.400 were known to the ancient Egyptians or the Hebrews. However, 0:14:26.760 --> 0:14:30.880 we do have a very early magnifying glass, or depending 0:14:30.880 --> 0:14:33.600 on who you ask, perhaps a fire starting glass, something 0:14:33.600 --> 0:14:35.840 that you used to refract the rays of the sun, 0:14:35.920 --> 0:14:38.440 you know, to start a small fire, you know, the 0:14:38.480 --> 0:14:42.160 kind of thing that children may sometimes do when trying 0:14:42.160 --> 0:14:45.280 to burn ants, hopefully not to ants, hopefully not. I mean, 0:14:45.960 --> 0:14:49.400 and you know one has to be careful. But at 0:14:49.440 --> 0:14:53.000 any rate, this particular lens, the Nimrud lens, is a 0:14:53.080 --> 0:14:56.200 three thousand year old crystal unearthed in eighteen fifty by 0:14:56.240 --> 0:15:01.440 Austin Henry layered in the Syrian palace of Nimrod. However, 0:15:02.200 --> 0:15:04.000 we were also not sure. It might have simply been 0:15:04.000 --> 0:15:07.640 a decorative element. It might not have been used. Uh 0:15:07.640 --> 0:15:10.040 and in any rate, it's not tinted. Okay, so we're 0:15:10.040 --> 0:15:12.240 not talking about sunglasses, right, but we are talking about 0:15:12.280 --> 0:15:14.960 like a crystal that may have been that people may 0:15:14.960 --> 0:15:18.400 have looked through. Now you have to ask you the question, like, 0:15:18.440 --> 0:15:20.480 to what extent did they just look through it because 0:15:20.520 --> 0:15:24.000 it was cool? Like what's more mystical than holding up 0:15:24.040 --> 0:15:27.560 some sort of you know, gleaming crystal even if it's clear, 0:15:27.960 --> 0:15:32.280 and watching how the world is distorted ever so slightly. Now, 0:15:32.320 --> 0:15:34.960 another thing that's worth noting is that we've been talking 0:15:35.000 --> 0:15:38.680 about lenses and tinted lenses, but obviously people came up 0:15:38.720 --> 0:15:42.000 with ways of protecting their eyes from the sun, uh 0:15:42.240 --> 0:15:45.520 having accessories beyond just their hands and their eyelids and 0:15:45.560 --> 0:15:48.960 stuff to protect their eyes from the sun long before 0:15:49.400 --> 0:15:52.840 there were there were tinted glass or plastic lenses or anything, 0:15:52.880 --> 0:15:57.960 for example, hats and umbrellas. That's obvious, yeah, But a 0:15:58.120 --> 0:16:01.040 much more ingenious and much more interesting one is what 0:16:01.120 --> 0:16:03.840 I want to mention the Inuit, and you pick people's 0:16:03.920 --> 0:16:08.040 of the northern circumpolar regions today Canada, Alaska, Greenland and 0:16:08.120 --> 0:16:12.280 Russia have for centuries made these ingenious devices known as 0:16:12.320 --> 0:16:15.520 snow goggles. Yes, and and I want to come back 0:16:15.560 --> 0:16:17.760 to what we said earlier about lumens before we get 0:16:17.800 --> 0:16:20.360 into this, because I think this really drives home the 0:16:20.440 --> 0:16:24.480 necessity that led to the invention. Uh So, in an 0:16:24.480 --> 0:16:27.880 indoor environment, a human is typically typically going to encounter 0:16:27.880 --> 0:16:31.120 four hundred six hundred lumens. That's the intensity of the 0:16:31.200 --> 0:16:35.000 light um and our comfortable level four loomens. It's it's 0:16:35.000 --> 0:16:38.440 gonna go up to round thirty five hundred. If you're 0:16:38.480 --> 0:16:41.280 in the shade on a sunny day, you're probably encountering 0:16:41.320 --> 0:16:44.200 around a thousand lumens sunny day out on say a 0:16:44.280 --> 0:16:46.880 highway or other reflective surface. You know, we all know 0:16:46.920 --> 0:16:48.680 what it's like to drive on like a really sunny day. 0:16:48.720 --> 0:16:51.400 You almost have to have shades. Uh, you're probably gonna 0:16:51.440 --> 0:16:54.600 do with something like six thousand or more lumens. Uh. 0:16:54.760 --> 0:16:57.400 Ten thousand lumens is the danger zone where you really 0:16:57.440 --> 0:16:59.520 have to start worrying about the health of your eyes. 0:17:00.240 --> 0:17:03.000 But a snow field on a sunny day, you're talking 0:17:03.760 --> 0:17:07.080 twelve thousand plus lumens. And this is where you enter 0:17:07.080 --> 0:17:10.359 the domain of potential snow blindness. Right. And this is 0:17:10.400 --> 0:17:13.560 of course because of the reflective power of white snow. Right, 0:17:14.080 --> 0:17:16.479 it can create almost a kind of double sun effect, 0:17:16.600 --> 0:17:20.280 sun above and sun below being reflected back up. Whereas 0:17:20.320 --> 0:17:23.120 you know, a normal patch of ground that's got say 0:17:23.160 --> 0:17:27.159 grass or just open soil, might reflect about ten of 0:17:27.200 --> 0:17:29.640 the UV ray is coming from the sun. Snow can 0:17:29.680 --> 0:17:32.439 reflect not quite a hundred percent, but something like close 0:17:32.480 --> 0:17:36.399 to ad of it. Nearly doubling your UV exposure. And 0:17:36.480 --> 0:17:39.240 so if you are, say living in in northern regions 0:17:39.280 --> 0:17:41.760 where there's a lot of snow cover, one thing that 0:17:41.840 --> 0:17:43.920 works in your favor is that for much of the year, 0:17:44.040 --> 0:17:46.880 the sun doesn't get super bright, right, it doesn't get 0:17:46.920 --> 0:17:49.520 super high in the sky, doesn't get super direct, but 0:17:49.760 --> 0:17:51.760 it will in certain parts of the year where there 0:17:51.840 --> 0:17:53.760 is still a lot of snow cover on the ground. 0:17:53.760 --> 0:17:57.000 So when you've got those things working together, say bright sun, 0:17:57.600 --> 0:18:00.480 heavy snow cover, maybe in the springtime when the sun 0:18:00.560 --> 0:18:03.119 is out high in the sky, proper eye protection is 0:18:03.160 --> 0:18:06.480 incredibly important. And not just because it's difficult to hunt 0:18:06.600 --> 0:18:09.360 or see where you're going when the sun's reflecting off 0:18:09.359 --> 0:18:11.679 the white snow and there's blinding glare and everything, but 0:18:11.720 --> 0:18:14.679 it's what you mentioned. There's this risk of snow blindness, 0:18:14.880 --> 0:18:18.359 which is also known as a photocarrotitis. So, as we 0:18:18.400 --> 0:18:21.800 mentioned earlier, part of natural sunlight is ultra violet radiation, 0:18:21.880 --> 0:18:25.160 and ultra violet radiation can damage the cornea. It can 0:18:25.240 --> 0:18:28.119 damage the conjunctiva, the outer surfaces of the eye, just 0:18:28.160 --> 0:18:30.720 like it can damage the skin. And this is why 0:18:30.720 --> 0:18:34.080 photocarrotitis is often described as something like quote sunburn of 0:18:34.160 --> 0:18:37.760 the eye. Symptoms include pain and feeling of having like 0:18:37.840 --> 0:18:41.840 irritants or foreign bodies lodged in the eye, tearing up, 0:18:41.920 --> 0:18:46.600 swelling and redness, light sensitivity, and sometimes even truly temporary 0:18:46.720 --> 0:18:50.000 loss of vision. That's where the blindness comes from. And 0:18:50.040 --> 0:18:52.320 so if you need to be doing stuff out in 0:18:52.400 --> 0:18:54.720 the snow where the sun is bright, this this is 0:18:54.720 --> 0:18:56.879 going to be a problem. And snow goggles fight this 0:18:56.960 --> 0:19:01.199 problem with a very smart design. They're typically a carved frame, 0:19:01.520 --> 0:19:06.120 usually made from animal bone or walrus tusks, sometimes from driftwood, 0:19:06.520 --> 0:19:10.000 or sometimes even from like strange materials like I saw 0:19:10.040 --> 0:19:12.320 one that I think was from baleen from a whale, 0:19:13.080 --> 0:19:16.320 and uh. This frame fits tight over the eyes so 0:19:16.359 --> 0:19:18.600 that light doesn't get in on the sides or the top, 0:19:18.920 --> 0:19:22.600 and then light is allowed to enter through two very wide, 0:19:22.800 --> 0:19:26.560 very narrow slots carved in the middle of the goggles, 0:19:26.680 --> 0:19:29.760 which are sometimes darkened on the inside with a material 0:19:29.840 --> 0:19:33.679 like soot. And these narrow slits allow the person wearing 0:19:33.720 --> 0:19:36.280 them to see without exposing their eyes to too much 0:19:36.280 --> 0:19:39.919 glare or UV radiation. And some alternate versions also have 0:19:40.320 --> 0:19:44.240 have multiple slits more like like shutter shades or Venetian 0:19:44.240 --> 0:19:47.720 blinds or something. They're not unlike the sort of novelty 0:19:47.920 --> 0:19:51.560 plastic nineteen eighties sunglasses. You know where they were where 0:19:51.600 --> 0:19:54.200 you just had you had no glass, no linbs, shutters 0:19:54.240 --> 0:19:57.960 these slits, yes, so shutter shapes which. Yeah, you look 0:19:58.000 --> 0:20:00.199 at the especially the nineteen eighties versions of the is 0:20:00.200 --> 0:20:02.640 and it's easy to just think this is ridiculous. This 0:20:02.760 --> 0:20:06.560 is the this is the sunglasses. This is I wear 0:20:06.880 --> 0:20:09.560 is a purely decorative element, and to a certain extent 0:20:09.640 --> 0:20:12.240 is true. But they do have a certain functionality as well. Yeah, 0:20:12.280 --> 0:20:15.600 and in many ways highly effective functionality. I mean this, 0:20:15.960 --> 0:20:18.479 if you don't have tinted glass to work with, this 0:20:18.560 --> 0:20:22.240 is a genius design. Yeah, and and the necessity that 0:20:22.320 --> 0:20:24.520 led to it, like like this would this would be 0:20:24.800 --> 0:20:29.280 the kind of environment that would necessitate sunglasses UM in 0:20:29.320 --> 0:20:31.480 a way that other parts of the world did not. 0:20:32.160 --> 0:20:34.080 All Right, Well, on that note, let's take a quick break, 0:20:34.280 --> 0:20:37.600 and when we come back, we'll discuss some more curios 0:20:37.600 --> 0:20:42.200 from the UH the history of invention UH in regards 0:20:42.200 --> 0:20:51.480 to the sunglasses. Alright, we're back now. Another frequently sided 0:20:51.800 --> 0:20:55.840 example of of sunglasses or early sunglasses used UH and 0:20:56.000 --> 0:20:58.359 involved them not being used to protect against the sun 0:20:58.960 --> 0:21:02.200 or perhaps any any way affect vision, but that they 0:21:02.200 --> 0:21:06.600 were allegedly used just to hide your eyes from others. 0:21:06.880 --> 0:21:10.000 This is this is a crucially important part of sunglasses. 0:21:10.280 --> 0:21:12.480 You could not ignore it. I mean, think of all 0:21:12.480 --> 0:21:15.040 the times you've worn sunglasses, and there are times where 0:21:15.040 --> 0:21:17.680 you wear them to protect your eyes. There are times 0:21:17.680 --> 0:21:21.000 when you wear them to to see better than high 0:21:21.200 --> 0:21:24.399 a light intensive environment. There are times when you do 0:21:24.440 --> 0:21:27.160 it to look cool. But there are times when say 0:21:27.440 --> 0:21:31.320 I've I've warned them, for instance on the train before uh, 0:21:31.480 --> 0:21:34.760 even when the train is underground, because it kind of 0:21:34.800 --> 0:21:37.880 makes me a little invisible. If I have my sunglasses on, 0:21:38.160 --> 0:21:43.840 my my earbuds in, then I am like less visibly present. Well, you, 0:21:44.119 --> 0:21:47.840 it means you can look around the world around you 0:21:47.880 --> 0:21:53.520 without ever unequivocally being caught looking at someone or something. Yeah, 0:21:53.680 --> 0:21:55.960 it's a natural human tendency to want to look around 0:21:56.040 --> 0:21:58.639 and see who's around you. Like, if you get caught 0:21:58.720 --> 0:22:01.760 looking at somebody, that's always awkward, especially if you've got 0:22:01.800 --> 0:22:04.280 some kind of social anxiety. You don't you don't want 0:22:04.280 --> 0:22:06.320 to like make that eye contact and be like, oh, 0:22:06.359 --> 0:22:09.000 we just both looked at each other at the same time, right, 0:22:09.040 --> 0:22:11.080