Thompson 1921: The Original Chicago Typewriter

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Subtitles by Neptune. Inspired by the infinite handsomeness of the video’s presenter. Hi guys, thanks for tuning in to another video on I’m Ian McCollum and I am here today at the Morphy Auction House– –Taking a look at what is probably one of the most iconic looking and recognizable firearms of all time. This is of course… …The Thompson Submachine Gun. Now, we’re going to take a look at the- the whole spectrum of the developement and the modification– –And the military and commercial use of the Thompson Submachine Gun over the course of a couple days here. And we are going to start today with the Model of 1921– –which is the first production Thompson Submachine Gun. So, the gun is of course named for John Thompson, General John T. Thompson. Who had a pretty distinguished career in the U.S. Military prior to World War One. He was fairly heavily involved in the adoption and the development of the 1903 Springfield (bolt action) Rifle. And during World War One he was recalled to service and ended up acting as the director of arsenals– –for the U.S. Military. So he was very much in tune with the arms development process, what the military was looking for, What the military was interested in, and how this whole system worked. And Thompson was very heavily interested in self loading firearms. Semi-Auto Rifles and Machine Guns. And, uh, even during World War One he put together some capital and created what became known as– –The Auto Ordnance Company. uh, And there were two projects that this company would work on. One was a semi-automatic rifle for U.S. Military Trials And one was would become the Thompson Submachine Gun. Now, both of these guns were based on a… …kind of a flawed physical principle… …An idea patented by a U.S. Navy Commander by the name of John Blish. He had noticed that Naval guns, screw-breech naval guns– –behaved differently with different charges of powder. And what he interpreted from this was that there was this Blish Principle, that dissimilar metals– –would have… different… coefficience of friction depending on the amount of pressure placed upon them. This didn’t really actually work in practice as it was applied to the Thompson Firearms– –but, the principle was patented, of course, you don’t have to prove that something works to patent it. And, uh, Thompson struck upon this concept as something he thought would be, uh, the perfect way– (corrects himself)–the perfect system to use to develop his semi-auto firearms. So, with the rifle– in fact, we have a couple videos about the 1923 Thompson Rifles. uh, [which didn’t end up doing all that well in military trials] And part of the outgrowth of that, or part of the side effects of that early development was, uh, One of Thompson’s engineers, a guy named Eickhoff– –Looking in– like, studying this Blish Principle and the functioning of the guns, And coming to the conclusion that this seemed to work a lot better with a pistol caliber cartridge– –than a full powered rifle cartridge like 30.06 (7.62×63mm) So, uh, he approached Thompson with this, and Thompson thought: “This would be a fantastic idea”(not a real quote) In fact, that instead of working on just a rifle they should develop– –A small handheld machine gun. Something that he, uh, (cute gibberish) “A trench broom!” That’s what we need, this is in World War One (1914-1918) uh, We want a gun that, you know, American Troops can jump into the trench and just hose it down– –Because, machine guns are clearly the wave of the future– –And Thompson was a bit ahead of his time… …or certainly, in tune with his time in recognizing that that’s where firearms development was gonna go. By the end of World War One uh, late 1918-early 1919 um, They had the first prototypes of what was called: 𝐓𝐡𝐞 𝐀𝐧𝐧𝐢𝐡𝐢𝐥𝐚𝐭𝐨𝐫 🔥🔥🔥 Which was–looked very much like a stockless, sightless Thompson Gun. Had two vertical grips, uh, and fed .45 ACP (11.43×23mm) From box magazines as well as drums. And was pretty much… …A trench broom. The problem was, of course, World War One was over. And so there wasn’t any… There wasn’t this huge market available– –There wasn’t this huge need for this sort of weapon anymore, so, they kept developing the gun. And, uh, in March of 1920 they actually put in, or signed a contract with the Colt Firearms Company– [The Colt Manufacturing Company] –To produce a run of Thompson Guns. So, I should say the Auto Ordnance Company was-was a pretty small company, there were half a dozen guys… (half a dozen means 6) …working for Thompson and they didn’t have a manufacturing facility at that time. They had a name, and they had the design but they had to contract out the actual assembly of the guns– –the manufacturing of the guns to someone else. And they picked Colt, very good name, you know, recognizable, high quality, Great! And they contracted with Colt to manufacture 15,000 of these guns. To be delivered within 15 months. Now, they didn’t– Auto Ordnance didn’t have a contract or uh, They didn’t have costumers for 15,000 guns but this is sort of like printing a book. uh, In order to get a good price on the gun, you have to manufacture it in scale. And so that is what Auto Ordnance did with its investment capital. They figured, “We’ll have this great gun and we can find people that will want it, and we can sell it, but we have to –Put in the money ahead of time to get the guns made. We can’t just manufacture 5 or 10 or 100 at a time as people order them” So, uh, Colt charged 44.56$ a piece for these Thompson Guns– ($44.56 in 1921 is worth $577 in 2019) –Which was pretty expensive at the time, this is not a cheap gun to make especially using Colt’s level of– –Quality and fit and finish and percision. And Auto-Ordnance would go on to resell those guns on the wholesale market– –They’d sell them to their distributors, their wholesalers uh, for, between 137$ and like 157$ a piece– –depending on the model. So…($137.00 in 1921 is worth $1,774 in 2019) Auto-Ordnance was making a substanstial mark up, you know, they took the cost of the gun, [for them]… …And they doubled that amount in profit margin. Which… these guns would end up on the final retail sales list… [sort of retail, these were pretty much just marketed to police and banks, really] ummm… The guns would cost 175$ to 200$, or even a little bit more depending on, again, options and model. ($175.00 in 1921 is equal to $2,266.28 in 2019) 175$ to 200$ on the retail market and that is a tremendous amount of money for the 1920’s. At the same time, you could buy a brand new car for 400$ to 500$. So, if you think about that in today’s terms, think about going out and getting not the fanciest car– –But like a brand new… Toyota Corolla or something, well, you could get a new car– –Or you could get 2 Thompson Submachine Guns. This is part- this is the large part of why these guns didn’t sell all that well. So we’ve all seen the basic profile of the Thompson but let’s take a closer look at we’ve really got going on here. So, this particular gun has a Cutts Compensator on it. Technically that makes this a model of 1921AC, The Cutts Compensator was designed by Col. Richard Cutts. uh, Who proposed it to Thompson in 1921 as a way to reduce muzzle climb and make the guns more easily– –shootable and more controllable. And, uh, Thompson agreed that it seemed like a pretty cool idea, Cutts ended up getting in on this with a 1$ per gun royalty. (14.31$ in 20169 And, uh, became a very popular part of the Thompson, So, in addition to manufacturing a lot of guns– –with these compensators, a lot of the prior 1921 pattern, just bare muzzle guns were eventually– -retrofitted with compensators like this one. On the right side of the reciever we’ll start to find some markings, uh… Auto Ordnance Corporation of course, marketed the guns, they didn’t actually do the manufacture– –but their name is on the reciever, put there by Colt. And then we have a selection of patents on here, That March 1915 patent is Blish, everything else on there is an Auto-Ordnance patent directly related to the Thompson Guns. We have that Thompson trademark bullet logo on top of the reciever. And then a whole slew of more markings on the left side. So ‘Thompson Submachine Gun.” ‘Caliber .45’ ‘Manufactured by Colt’, right there. And our model and serial number up here, on the front left side, So it’s a model of 1921, serial number 10,000. Remember that these were manufactured at one go– –over the course about a year or so by Colt. So they took a long time to sell, but they were all pretty much made at the same time. Our controls are all here on the left side, and these are controls that kind of fit what you might expect from– –what is really a World War One era Submachine Gun– –People look at the Thompson and they think 1920’s, 1930’s, in reality this gun was designed in 1918-1919– –And so, it doesn’t benifit from a lot of the development and expertise that came about– –or experience that came about with submachine guns through the next decade or two. So, we have two selector switches here. We have one for Safe and Fire. Uh, you can only rotate this back when the bolt is cocked, which it is. And then you have a seperate selector lever for semi-auto– (one shot per trigger pull) –and full-auto, (RATATATATATA mode), so… That’s full-auto right there, and then we rotate that around… …for single shot, this is not the most ergonomic thing to use, although, this… …not bad. The magazine release is particularly unusual for folks today– –It’s kind of a unique style, uh, you push this tab up… …and it pulls this back in, which allows the magazine to come out. There is a hole in the back of the magazine. Notice also that the mag has this big T-shaped, uh, control on the back of it. That magazine slides up into this matching T-shaped channel, and when I depress the magazine release… …this big old round plunger goes back into the trigger guard, so… That’s how the magazines lock into place. Note that there are also these two grooves cut, uh, in the magazine well itself… …those are for the drum magazines. So the 2 patterns of magazine that were originally manufactured and offered with the Thompson Guns were– 20 round, uh, double stack, double feed box magazines. These were– these retailed by– well, as of 1928 these retailed for 3$ apiece. ($3 in 1928 is worth $43.57 in 2019) And they sold wholesale for 2.25$ ($2.25 in 1928 is worth $32.67 in 2019) uh, Just to put this in perspective, About this time, a worker in an automotive factory would be making basically between 0.50$ to 0.90$ an hour. (0.50$ in 1921 is worth $7.15 in 2019) uh, So, you know this magazine is gonna cost 2/3 of your daily pay, maybe half of your daily pay depending– –on what you were getting paid. The drum magazine– (oh yeah baby) –Held 50 rounds. This is actually fairly com– fairly similar in function to a Suomi (KP-31) drum. uh, And these wholesaled for 15.75$ and retailed for 21$. ($15.75 in 1928 is worth $228.72 in 2019) This was really a remarkably expensive, uh, magazine. So, we can open this up by popping the winding lever off. This one’s kind of tight, there is a peg here that winds up the top cover. There we go. uh, Originally from the factory this would have been nickel plated and nice and shiny. This is a Colt manufacture one, you’ll also find drums made by Auto-Ordnance in Bridgeport. Which– we’ll get to Bridgeport, uh, in a later video. You’ll also find West Hurley guns, which are like post-WW2 production. And you’ll find Chinese reproduction knockoff drums. So, this is, as being a Colt Drum this is the best. And by the way, this here at Morphy’s is not included with this particular gun. So, uh, looking at it here you load this by setting cartridges uh, primer down. You know, case head down, nice and flat. (like Earth) In each of these slots, just the one row right there, the one row there, And then two rows in the rest. Fits 50 rounds, you then, put the D cover back on. And there is a clock style spring inside here that you then wind up. How much do you wind it? Well, For a 1921 model, you’d wind 11 clicks. For a 1928 model, you’d wind 9 clicks. Uh, this of course was manufactured after 1928. Note that they call this a type ‘L’ drum, L being the Roman Numeral for 50. Not long after production started, they also introduced a ‘C’ Drum. You may figure out that’s the Roman Numeral for 100– –And yes, it was a larger 100 round Drum magazine. (WHAT) Those were not very popular, uh, they were awkward, they were very large, they were bulky, uh, They weighed over 10 pounds (4.5 Kilos) for just the magazine when loaded. So you combine that with over 11 pounds for the gun itself– (21 lbs=9.5 Kilos) And– you like– That’s a lotta weight to be toting around. (the gangsters must have been buff from carrying it) So, uh, the 50 round Drums were much more popular than the 100’s. (Now for the drum magazine!) The Drum magazine fits in the gun a little big differently than the stick mags. It doesn’t actually use this button to hold the Drum in, instead you have the two rails that slide into these– –Two grooves. And then you have this slot right here. That actually locks in place around this portion of the magazine catch. We’ll go ahead and put it in right here… You want the winder in front. And this is going to slide into the gun… right up to there, And then when we push it the rest of the way in… …That lug locks in… …right there! So that’s how the Drum is held in place. (If disassembly bores you, just skip to 21:50 when it ends.) Last point I wanna touch on with the magazines before we go to disassembly– –Is that despite being an open-bolt submachine gun, the Thompson actually locks open on an empty magazine– –Which is actually kinda handy. Most submachine guns when it’s empty your last trigger pull– [or holding the trigger] drops the bolt forward– –And then you have to re-cock it when you put in a new magazine– –Not so with the Thompson. So… For disassembly we’re wanna take the magazine out. Uh, we want the bolt to be forward like so. We need to make sure it’s in full-auto mode. [which this is] And then the first thing we’re going to do is actually just take the butt stock off. uh, The butt stocks are quick detachable, just push the button. And it slides off its little rail on the bottom. By the way, they did put the serial number of the gun on the bottom of the trigger frame here. uh, Where you can only see it once you take the butt stock off. Next up, we are going to remove the bottom frame– the trigger guard fire control assembly. We’re gonna do that by pushing in this button, holding the trigger down and sliding the grip assembly– –Backwards off of the reciever. There we go, some of these are really tight, some of them are nice and smooth (like my dance moves) Remember to hold the trigger down, that prevents the sear from locking up on any of the internal parts– –While you are doing this. One of the really obvious signs that you have a 1921 Thompson is this large diameter recoil spring back here. uh, That has a little plunger pin that’s gonna come all the way out the back of the reciever. So we’ll go ahead and push that in… Slide it forward, lift it up… Pull the recoil spring out of the gun… Next we can pull out so– the bolt elements. There’s 3 parts there, we’re gonna pull the bolt back to here… …And we can lift it out, so that’s the bolt body. Then, I’m going to– I’m sliding this by the charging handle down here. Slide this back to this point. And then I can pull out the Blish Lock. (inaudible) A grip on it, there we go, that’s the actual Blish Lock. And then we have the Actuator Handle, slide it back to this position… …Right here. There we go. And then it lifts up, the charging handle comes out through that round cut. Now you have stripped the internals from your Thompson Gun. I will point out there’s one last bit inside here which I am going to leave inside here. This is one of the less typical sorts of buffers that you’ll find in Submachine Guns in general. There is this piece of spring steel wrapped around the inside of the reciever… …Which you can grab those 2 wings, pull ’em together and pull this whole thing out– –But it actually has two little felt pads on either side– –That push in the bolt in the end of its travel. So, Not oiler pads, those are actually recoil cushions. So that’s it for disassembly, what you’re left with now is this long reciever section– –Which is a pretty complex piece, this is part of why the gun was so expensive to make. uh, There are a lot of different cuts, uh, to be had in-in this reciever. And of course the rear sight doesn’t help with the cost. I should point that out before we go any further. The 1921 Thompon series used a Lyman rear sight. uh, Which has all sorts of adjustabiliy, you can flip it up, you’ve got an aperture sight, You’ve got a rear notch sight here. This was all– honestly this was all wasted on the Thompson Submachine Gun. It didn’t need anything remotely like that level of rear sight. But, that’s uh what they would go ahead and use, so… That would go away later on, we’ll touch on that in a later episode. Of course there are a nice big pair of wings here to protect that Lymann rear sight. One more thing I will take off is the front vertical grip, we can do that, There is a screw right here in the bottom. Just…. unscrew that. I apologize for the garbage truck outside. Here we go, nice long bolt comes out. And there is our front grip. So this thing, when it’s installed… Looks like it’s just hanging down here really delicately below the barrel. In actuallity… that’s a pretty stout bar of steel here from the reciever out. And it’s got this little tab that rests up against the barrel to help support it. You’re not breaking the front grip off of this thing. So the way that this works, we have an actuator, it’s called here, uh, Which is our charging handle and it’s got this slot to control movement of The Blish Lock– –Which is brass. uh, Remember the Blish Principle was based on uh, it’s kind of a wierdness in coefficeint of– –Friction between 2 dissimilar metals. So we have steel in the reciever and brass in the actual Blish Lock. And the idea is… we put this guy down in the gun. Here we go, that comes forward, we have this nice helpful ‘UP’ label here. And I wanna drop that in that direction. So now, when the gun’s– (corrects himself) when the bolt’s all the way forward– [of course the bolt is up here and out of the gun at the moment] When the bolt’s all the way forward, this Blish Lock lifts up in… …THIS angled track. And before the bolt can move backwards, this Blish (cute gibberish) Lock has to– –Slide down that angled track, and then it’s freed up here and it can move backwards. The–The Blish Principle says that uh, under– when the cartridge is fired, when there is pressure in the chamber– –Actively pushing on the bolt face… There will be enough friction that these 2 pieces, The Blish Lock and The Reciever will lock together– –And they won’t move. Once the bullet leaves the barrel, then the pressure reduces and when you have less pressure, The coefficient of friction changes and then this piece cam moves. That’s The Principle (Didn’t understand that? Neither did John Blish) In reality, this functions because there is enough weight, uh, and just a tiny bit of delay while this actually– –Slides because there is friction between these 2 parts. uh, That friction and the weight allow this to operate as effectively a blowback Submachine Gun. Not strictly speaking technically blowback, although that would come later in the Thompson Evolution which– –We’ll get to in a later episode. uhm, We can go ahead and put the rest of the bolt body back in. uh, Note that there is a big open space here, uh, that was used for the recoil spring. And then you have a diagonal cam slot here which is where The Blish Lock sits. So if I put this back in… *puts this back in* Like so, now bolt goes forward, see the Lock lifts up, uh, These surfaces right here, they’re this surfaces right here– –Is your sear cut, so when the bolt is back the sear in the trigger group right here. That’s locked against this, which holds it in place. When you pull the trigger, that sear drops– –Which allows the bolt to go forward. Locks… “Locks” Fires… Cycles back. And that’s everything. There’s your–your firing process. So here’s how this looks like when it’s assembled out of the gun. uh, You can note that the actuator here, because of this controlled cut in it, It serves to uhhh…. when you pull the handle back it lifts the Blish Lock. And the idea here was when you charge the gun manually you disengage The Lock– –And then you can just pull the bolt backwards. um, But as long as this remains forward, now The Lock is engaged such as is, um, You know, to the extent that it is a lock. It’s really just a slight addition to a delaying system. But, you can override it, disable it, by using the charging handle. So what did happen with the 1921 Thompson? Well, uh, the U.S. Air Service actually did test the gun in 1921 and ’22. They ended up rejecting it ’cause let’s be honest, The Thompson’s not really all that well suited to adapt to– –Aircraft use. By the end of World War One, uh, Rifle caliber machine guns in aircraft are very standard and well accepted– –And the idea of scaling back from that to a .45 ACP aircraft gun, eh, that doesn’t really make a lot of sense. And, on top of that, the Air Service had issues with the Drum Magazines. And of course they wanted the large capacity magazine for use in an aircraft. So, that was out. In 1923, Auto-Ordnance went on a big European sales tour to try military interest ‘drummed’ up. (get it?) They went to England, France, Belgium, Spain, and they got kind of… …Nothing from it. um, There was even an attempt to develop a military model of the gun, they made some prototypes of it– uh, Right at this time, had a longer 16 inch (0.4 Meter) barrel. Had a bipod on it. (WHAT) They actually rechambered it for a more powerful cartridge, the .45 Remington Thompson, Or Thompson-Remington. uh, That went nowhere, no one was really interested in that. Although it is a gun that looks pretty cool. (Like Ian over here) So… That went out the door, um, they attempted to sell them to the Royal Irish Constabulary, that didn’t work out. Ironically, one of the first uh, adopters of the Thompson was actually the Irish Republican Army [or the predecessor of the IRA] uh, There were 4 attemps to smuggle Thompson Guns in some quantity into Ireland. uh, 3 of those attemps worked, 1 of them didn’t, that became a whole giant politcal uh, scandal. Which can be covered… We’ll talk about that in a seperate video And it’s interesting actually to this day some of the VERY EARLY Thompsons that were ever made… …are actually probably still in Ireland or were destroyed at some point, uh, during the conflict between the– –The British and the Irish. So, there… Thom– Thompson’s having trouble selling these guns. Of course it was designed for a military market. The war’s over. This–these 15,000 guns that they ordered from Colt were just kind of slowly trickling out the door year by year. The first break with the U.S. Military finally came in 1926. And uh, that was because the U.S. Postal Service was having a lot of trouble with postal trains getting held up. And so they purchased 200 Thompson Guns– (FINALLY) uh, To supply to U.S. Marine Corps Troops who were going to be guarding U.S. Postal trains. And so these– these guns, they were purchased by the Postal Service ended up property of the U.S. Marine Corps. uh, And the Marines 𝐋𝐨𝐯𝐞𝐝 𝐭𝐡𝐞𝐬𝐞 𝐭𝐡𝐢𝐧𝐠𝐬. Now I think It’s important to point out that the character of the Marine Corps was a little bit different– –Or the nature of the Marine Corps was a bit different then, perhaps than it is today. Or different than what people think of it today. The Marine Corps was a very small, uh, branch of the military and it served in many ways kind of like– uh, the Expeditionary Corps of-of other, uh, nations When there was trouble going down somewhere, like Nicaragua, or Panama, or Cuba, And you needed just a small force of-of guys to go enforce American foreign policy, The Marine Corps was often the units, the branch that was sent. And so, The Marine Corps in the 1920’s was this unit of professional career soldiers, Many of them with extensive uh, small scale combat experience. They were– they were the hardened professional Corps of much of the U.S. Military. And… you give these, basically grizzled veteran soldiers, used to carrying 1903 Springfields– –You give them, Thompson Submachine Guns, And they fell in love with those things. They would take them down to Nicaragua in 1926 I believe, or ’27. uh, They were great in the Jungle in Nicaragua. They took them to China, when the U.S. Marine Corps was deployed in China. uh, On the Yangtze, they loved them there. And this was finally sort of a break for the Thompson Company. They didn’t buy many, you know, we’re talking a couple hundred guns, but– That would be the seed that would develop into mu– the ultimate greater success of these guns. Now we will pick up this tale in the next segment, where we’ll be talking about the 1928 Pattern Thompsons. And, uh, increase finally a little bit more, yet more interest from the U.S. Military. So, uh, until then, of course This Thompson and all of these behind me are all coming up for sale– –At the Morphy Auction House here in their upcoming fall firearms auction. (this message was written after the auction ended). So if you take a look at the description text below you will find a link to– –Which will uh, have some links, over to Morphy’s catalogue and you can check out their descriptions– –Their uh, detailed pictures, uh, everything you’d need to know, their price estimates. Anything you’d need to know about on this Thompson and the others in the Auction. Thanks for watching. Subtitles submitted to Forgottenweapons on 7th of February 2019 by Neptune. Updated 4th of August 2019. uwu


  1. Excellent video from beginning to end. You are clear spoken and easily understandable. I wish I owned one and knew more about the mechanics and take down then not only would I know what it is you were saying, but I might understand you as well!! Well, Mr. Thompson did eventually develop a fanatic following. Three well known admirers were, Frank Nitty, Babyface Nelson, and John Dillinger.

  2. I have always wanted one of these but of course being Canadian we are not allowed. But there are a lot of us That don't pay attention to our useless so-called leaders

  3. I know a guy that found one of these inside the wall of a building he was rehabbing. It was stamped with the date 1921,with the drum mag on it. This was in Chicago an at the time no other collectors had one in working condition. This was about 12 years ago.

  4. what Ian is doing for the documentation of classic firearms is unrivaled today….. appreciate it while you can, before this video platform also outlaws it. he is an invaluable asset for up and coming firearms community new comers ! you are why i became a class 07 FFL!,…..
    and also followed my dream in today's environment


  6. That's a great video, thanks broski ! I heard regular u.s.a citizens could buy them from sear-robock catalogs. is that true? beautiful man. If you have time, ( give us a video about the: B.A. R., that's one of my favorites also. thanks a million for your interest in old school firearms and weapons ! you rock. ! I'm ex-Army, I've always been fascinated about older weapons. You did a great job on this project! Thank You !

  7. 1921 Thompson SMG
    "The Chicago Typewriter"

    Rating: 3/10

    Does not actually type the alphabet or processes text documents on paper. Still, +3 because it was useful for getting rid of my boss in the office. Will recommend to your office for use.

  8. Hi Ian. I’ve just noticed that your captions have been transcribed professionally, and include a net present value for dollar figures you give in the video. Impressive!

    Do you get this done for all your videos? Do you do this yourself or do you employ a transcriber?

    Amazing work as always. Cheers.

  9. I acquired one of these when I was a teenager, my dad took and sold the clip, so I sold the gun. I didn't know at the time I could have used a banana clip in place of the drum ☹?

  10. What a beautifully machined gun compared to the war models. Amazing that Colt could produce that for $44 and still make a profit.

  11. Damn, how you not gonna shoot a master piece like that, I know it's not your but come on man. Also, how much does that auction for?

  12. You don't have to go ahead unless you have asked for permission first. Don't be superfluous. People will take you more seriously if you can speak like you didn't learn English from MTV.


    A. Robust.
    Speaker of English.

  13. Ian, you scoundrel!

    Having us believe that the Morphy Auctions logo was a decal on the wall when in fact it is merely a product of post-production!

    You sir, are a scoundrel of the highest order!

  14. ???? support the Patriots???? you think that weed Ian someone running across my roof at night i seen it like at the corner of the eye not fucking around

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