# If you could travel to the year 1820, how could you prove you were from the future? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [June 2, 2020, 4:03pm UTC](https://boards.straightdope.com/t/if-you-could-travel-to-the-year-1820-how-could-you-prove-you-were-from-the-future/854931 "2020-06-02T16:03:34Z")\ **Posts on this page:** 20\ **Page:** 9
**Author:** ![Elmer\_J.Fudd](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/elmer_j.fudd/32/1211_2.png) [@Elmer\_J.Fudd](https://boards.straightdope.com/u/Elmer_J.Fudd)\ **Post date:** [June 7, 2020, 1:46am UTC](https://boards.straightdope.com/t/if-you-could-travel-to-the-year-1820-how-could-you-prove-you-were-from-the-future/854931/161 "2020-06-07T01:46:15Z")
Convincing fortune tellers were a dime a dozen in 1820. Even the most gullible people of the time would scoff at you for claiming you were a time traveler rather than just a another mystic. ---
**Author:** ![Johanna](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johanna/32/8318_2.png) [@Johanna](https://boards.straightdope.com/u/Johanna)\ **Post date:** [June 7, 2020, 2:44am UTC](https://boards.straightdope.com/t/if-you-could-travel-to-the-year-1820-how-could-you-prove-you-were-from-the-future/854931/162 "2020-06-07T02:44:31Z")
I have two ideas that would probably work: Discover Neptune! Just memorize its orbital data and its position in 1820 to tell them where to point the telescopes. _Désolée, monsieur Le Verrier!_ Draw up the periodic table of elements. Show how they sort themselves by chemical properties. 1820 was right around the middle of the most active element-discovering time. New elements were being discovered right and left. Show how the periodic table predicts the properties and atomic weight of elements that haven’t been discovered yet—then get those predictions confirmed. Go to Ytterby, Sweden, dig up the rare earths, and wow everybody. Tell them how the gaps in their current list of elements will be filled in. ---
**Author:** ![adaher](https://avatars.discourse-cdn.com/v4/letter/a/dec6dc/32.png) [@adaher](https://boards.straightdope.com/u/adaher)\ **Post date:** [June 7, 2020, 3:21am UTC](https://boards.straightdope.com/t/if-you-could-travel-to-the-year-1820-how-could-you-prove-you-were-from-the-future/854931/163 "2020-06-07T03:21:38Z")
> [@eschereal](#): > > I am not convinced of that. We have very little to go on besides written texts, which are, by nature, formal. I believe that argot and casual speech was very common, the stilted formal manner less so. Still, adapting to the manner of speech of the day would probably take more than a day or two. Among poorer communities, I’m sure you’re right. But the language and culture of the upper classes, which presumably you’d need to endear yourself to to thrive, is pretty well chronicled. ---
**Author:** ![Pardel-Lux](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pardel-lux/32/20182_2.png) [@Pardel-Lux](https://boards.straightdope.com/u/Pardel-Lux)\ **Post date:** [June 7, 2020, 8:25am UTC](https://boards.straightdope.com/t/if-you-could-travel-to-the-year-1820-how-could-you-prove-you-were-from-the-future/854931/164 "2020-06-07T08:25:09Z")
Thinking further about this thread and having reached the conclusion that time travel is only possible in one direction (I myself am travelling towards the future right now at the rate of one second every second, a rate that, it seems according to relativity, can be accelerated or decelerated, but not reversed) I wonder if the right question to ask is not so much how do _I_ convince _them_ that I am from the future but rather how they convince me that this is not an elaborate prank. I would try to find out how they have pulled this trick off and why they have wasted so much money and ressources for such a puerile endeavour. Those efforts were no doubt worthy of a better cause. ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [June 7, 2020, 9:36am UTC](https://boards.straightdope.com/t/if-you-could-travel-to-the-year-1820-how-could-you-prove-you-were-from-the-future/854931/165 "2020-06-07T09:36:22Z")
> [@Johanna](#): > > I have two ideas that would probably work: > > Discover Neptune! Just memorize its orbital data and its position in 1820 to tell them where to point the telescopes. _Désolée, monsieur Le Verrier!_ I thought advanced preparations were not allowed. > [@](#): > > Draw up the periodic table of elements. Show how they sort themselves by chemical properties. 1820 was right around the middle of the most active element-discovering time. New elements were being discovered right and left. Show how the periodic table predicts the properties and atomic weight of elements that haven’t been discovered yet—then get those predictions confirmed. Go to Ytterby, Sweden, dig up the rare earths, and wow everybody. Tell them how the gaps in their current list of elements will be filled in. That might eventually convince people, definitely not an immediate thing. But most people don’t have the periodic table memorized well enough to pull this off. Nor are they that familiar with the history of the discovery of the elements to make those predictions. And as far as Ytterby sample, the rare earth elements were some of the most difficult elements to isolate among those discovered in the 19th century. It took a lot of painstaking work to separate out the very similar metals. And even then, there were lots of claims of discovery that turned out to be wrong. Unless you’re already a chemist, it’s unlikely you could do anything with the sample. There is an astronomical prediction that probably most people could make. The distances to the stars was not known at all in 1820. Predict that Alpha Centauri is the closest star and that it’s 4.3 light years away. Some people could also predict that Sirius is twice that far (8.6 ly), but that’s not as well known a fact. Predicting that Sirius is a double star would also be a good one. (Personally, I could produce a lot more astronomical facts off the top of my head, but I’m not your typical time traveller.) These predictions might convince the relatively small subset of people who studied the stars, but would they convince the general populace? Hard to say. ---
**Author:** ![Author\_Balk](https://avatars.discourse-cdn.com/v4/letter/a/e0b2c6/32.png) [@Author\_Balk](https://boards.straightdope.com/u/Author_Balk)\ **Post date:** [June 7, 2020, 2:04pm UTC](https://boards.straightdope.com/t/if-you-could-travel-to-the-year-1820-how-could-you-prove-you-were-from-the-future/854931/166 "2020-06-07T14:04:43Z")
I may be mistaken… I think if someone from 2220 came to 2020 could prove they were from the future, if the person knew who their 2020 ancestors are. Wouldn’t the DNA prove they are descendants of those people? I don’t think that would work in 1820 since this was before James Watson. ---
**Author:** ![eschereal](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/eschereal/32/18939_2.png) [@eschereal](https://boards.straightdope.com/u/eschereal)\ **Post date:** [June 7, 2020, 3:39pm UTC](https://boards.straightdope.com/t/if-you-could-travel-to-the-year-1820-how-could-you-prove-you-were-from-the-future/854931/167 "2020-06-07T15:39:04Z")
> [@Pardel-Lux](#): > > I wonder if the right question to ask is not so much how do _I_ convince _them_ that I am from the future but rather how they convince me that this is not an elaborate prank. Well, you could travel to central NH and look for the venerable rock formation known as the “Old Man of the Mountain”. For your friends to fake that would be quite impressive. Or you could go to the much greater effort of traveling to the PNW to observe Mt St Helens in her ten-thousand-foot glory as a few of us remember – getting there, however, would probably pose a daunting challenge in 1820 that could well kill you or leave you totally exhausted and no longer interested in the overall exercise. I think what I would do is the “easiest” endeavor: find a fairly competent craftsman who can help me build a [rogallo-style](https://en.wikipedia.org/wiki/Rogallo_wing) hang glider. Once you get a model that functions properly, even that relatively crude (by contemporary standards) design can perform impressively on a day that has good thermals. ---
**Author:** ![Pardel-Lux](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pardel-lux/32/20182_2.png) [@Pardel-Lux](https://boards.straightdope.com/u/Pardel-Lux)\ **Post date:** [June 7, 2020, 5:08pm UTC](https://boards.straightdope.com/t/if-you-could-travel-to-the-year-1820-how-could-you-prove-you-were-from-the-future/854931/168 "2020-06-07T17:08:58Z")
> [@eschereal](#): > > Well, you could travel to central NH and look for the venerable rock formation known as the “Old Man of the Mountain”. For your friends to fake that would be quite impressive. Or you could go to the much greater effort of traveling to the PNW to observe Mt St Helens in her ten-thousand-foot glory as a few of us remember[…] I told you I was quite impressed by the lengths those rascals have gone to prank me, I just think they should have pursued a worthier goal. ---
**Author:** ![Thudlow\_Boink](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/thudlow_boink/32/320_2.png) [@Thudlow\_Boink](https://boards.straightdope.com/u/Thudlow_Boink)\ **Post date:** [June 7, 2020, 5:11pm UTC](https://boards.straightdope.com/t/if-you-could-travel-to-the-year-1820-how-could-you-prove-you-were-from-the-future/854931/169 "2020-06-07T17:11:27Z")
> [@Author\_Balk](#): > > I may be mistaken… I think if someone from 2220 came to 2020 could prove they were from the future, if the person knew who their 2020 ancestors are. Wouldn’t the DNA prove they are descendants of those people? I don’t think that would work in 1820 since this was before James Watson. Can DNA testing tell the difference between ancestors and relatives? ---
**Author:** ![eschereal](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/eschereal/32/18939_2.png) [@eschereal](https://boards.straightdope.com/u/eschereal)\ **Post date:** [June 7, 2020, 5:26pm UTC](https://boards.straightdope.com/t/if-you-could-travel-to-the-year-1820-how-could-you-prove-you-were-from-the-future/854931/170 "2020-06-07T17:26:24Z")
> [@Thudlow\_Boink](#): > > Can DNA testing tell the difference between ancestors and relatives? Probably, because, by 2220, assuming a straight technological track (not necessarily a viable assumption), _everybody_ will be at least a little bit GMOs. ---
**Author:** ![iamthewalrus\_3](https://avatars.discourse-cdn.com/v4/letter/i/258eb7/32.png) [@iamthewalrus\_3](https://boards.straightdope.com/u/iamthewalrus_3)\ **Post date:** [June 7, 2020, 6:34pm UTC](https://boards.straightdope.com/t/if-you-could-travel-to-the-year-1820-how-could-you-prove-you-were-from-the-future/854931/171 "2020-06-07T18:34:42Z")
> [@Pantastic](#): > > I notice, again, the distinct lack of any specifics of what you’re going to ‘jump right in’ and do. There’s just this assertion that your future knowledge would be really handy… but nothing about what future knowledge would actually do for you. I mean, what game are you even going to be a player at? Name the ‘low hanging fruit’ off the top of your head, and then we can look up and see if it was even low hanging fruit or not. It boggles the mind. The first thing off the top of my head is that I can write a modern hypertext implementation close to a decade before most people had seen one. I can also write clones of the last four decades of hit computer games and personal productivity software. I can write a semi-decent description of the ARM instruction set. I’m aware enough of as yet undiscovered talent in the industry I could align with. Page, Brin, Ive, Cook, Carmack, Zuckerberg. Knowing just _one_ of those names and where they went to college is a well-defined path to wealth and influence. Looking briefly at the [timeline of algorithms](https://en.wikipedia.org/wiki/Timeline_of_algorithms#1980s) starting in the 1980s, I can describe in detail and write implementations of LZW, splay trees, lock-free data structures, simulated annealing, page rank (hmm, I wonder if that’s worth any money). Not all of them by any stretch, but, like, maybe enough to change the world? It’s hard for me to imagine any reasonably competent software developer being thrown back in time to the 1980s and not advancing the field dramatically. I believe that I could reasonably write thousands of pages of (mostly correct) information about modern devices and science that was generally unknown in the 1820s. I’m obviously not going to take the hundreds or thousands of hours it would take to do so here for the sake of a message board. I tossed out a few, and from what I can tell, of the two you’ve engaged with (electric light bulb and vulcanization), you think that one is totally not feasible, and the other maybe is. That seems like a pretty good success rate! Also I’d be curious what you think about my cite on the vacuum pump. Looks to me like a vacuum pump sufficient to manufacture Edison bulbs was absolutely within the tech of the 1820s. > [@](#): > > Vulcanization looks like it might actually be something that could have been accomplished decades earlier, and you might well convert the fortune behind the Goodyear Blimp to the Walrus Blimp if you manage to get it working in 1820 instead of a decade later. But the vast majority of things just aren’t, AND most people don’t have any idea which are and which aren’t. I mean, doesn’t the fact that of the maybe 1 dozen or so ideas I threw out with a few minutes thought, one looks like a pretty good path to major success support my theory really well? In ten minutes I thought of something I could do decades early? How many feasible ideas could I come up with given a few days or months of thought? ---
**Author:** ![Little\_Nemo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/little_nemo/32/3120_2.png) [@Little\_Nemo](https://boards.straightdope.com/u/Little_Nemo)\ **Post date:** [June 7, 2020, 6:42pm UTC](https://boards.straightdope.com/t/if-you-could-travel-to-the-year-1820-how-could-you-prove-you-were-from-the-future/854931/172 "2020-06-07T18:42:21Z")
> [@Author\_Balk](#): > > I may be mistaken… I think if someone from 2220 came to 2020 could prove they were from the future, if the person knew who their 2020 ancestors are. Wouldn’t the DNA prove they are descendants of those people? I don’t think that would work in 1820 since this was before James Watson. That part about knowing who your ancestors were two hundred years back is a big obstacle that you passed over pretty lightly. ---
**Author:** ![Pantastic](https://avatars.discourse-cdn.com/v4/letter/p/3bc359/32.png) [@Pantastic](https://boards.straightdope.com/u/Pantastic)\ **Post date:** [June 7, 2020, 6:51pm UTC](https://boards.straightdope.com/t/if-you-could-travel-to-the-year-1820-how-could-you-prove-you-were-from-the-future/854931/173 "2020-06-07T18:51:06Z")
> [@XT](#): > > At any rate, you have asserted that nitrogen wouldn’t work, but I haven’t seen you actually say why. And nitrogen isn’t exactly the only option. You have also asserted that a vacuum pump wasn’t possible, and myself I’d go with an inert gas as my first try, but I’m not convinced that an adequate vacuum isn’t possible. In 1850 Joseph Wilson Swan created a light bulb by enclosing carbonized paper filaments in an evacuated glass bulb, but wasn’t able to get a good enough vacuum with the technology then, and it took him until the 1870s to be able to make a bulb he was happy with (though he didn’t beat out Edison in the commercial market). In 1874 Henry Woodward and Mathew Evans filed a patent for lights made of carbon rods in electrodes in glass cylinders filled with nitrogen, which is the route you’re saying you’re sure would succeed. But with 54 more years advancement in tools and other engineering than you’d have in 1820, they failed to commercialize the lights. They eventually sold the patent to Thomas Edison, who elected to continue his work on and commercialize vacuum based bulbs rather than use their already-made nitrogen based bulbs. So I base it on the fact that historically actual people who knew the tools and resources available to them and knew a lot more about the topic than you do tried exactly what you’re proposing and didn’t manage to make it work. Thomas Edison, the guy who’s work you’re trying to use to jump start a bulb in 1820, HAD A WORKING NITROGEN BASED BULB but elected to do his famous 10,000 failures at making an incandescent bulb for commercialization instead. I’ll take ‘multiple smart people tried to make this work and failed to do so’ as much stronger evidence than ‘some guy who didn’t even know what material the first light bulb used’ thinks it must be easy but can’t give any more detailed argument than that. And I will note that you’ve neglected to answer the 1980 software developer piece again. What software are you going to write with your vague knowledge of what happened later on, familiarity with C (but unfamiliarity with the hardware of the time) that it going to make you make you a lot of money or revolutionize the industry? It’s easy to assert that future knowledge of what works makes it easy to succeed, but it’s difficult to see exactly what would work. ---
**Author:** ![Pantastic](https://avatars.discourse-cdn.com/v4/letter/p/3bc359/32.png) [@Pantastic](https://boards.straightdope.com/u/Pantastic)\ **Post date:** [June 7, 2020, 7:28pm UTC](https://boards.straightdope.com/t/if-you-could-travel-to-the-year-1820-how-could-you-prove-you-were-from-the-future/854931/174 "2020-06-07T19:28:53Z")
A couple of things about bringing back details (I’m not disagreeing with the post I’m quoting): > [@UltraVires](#): > > I suppose it would take little details. Suppose someone in June, 2019 came to you and said that starting in February to March of 2020 there would be a pandemic called Covid-19… Will ‘Covid-19’ be the name that sticks with the current pandemic for 200 years? ‘Spanish Flu’ has stuck with the 1918 flu in America for 100 years, but Covid-19 sounds a little too clinical to hang out for the long run. It’s quite possible that the name someone knows it by in 200 years would not be the specific name we’re used to. If the name that sticks is just a generic ‘coronavirus’ or something that sounds even more vauge, then the prediction becomes a lot weaker. People have been predicting a pandemic coming soon for about as long as there have been humans, and specific predictions about flu and corona viruses for decades, so something non-specific doesn’t require future knowledge. > [@](#): > > Then, at the beginning of June, the world would learn that a man named George Floyd was killed by a Minneapolis police officer by kneeling on his neck and there were widespread protests across the country. George Floyd is a good, specific detail. But what are the odds that his name specifically is what someone from 200 years from now remembers? If you predict ‘widespread protests in the US because a black man was killed by a cop’, that’s sort of like predicting 'unrest in the middle east - it’s not really a prediction. But if the time traveler remembers the wrong black name and mentions Rodney King, Eric Garner, Michael Brown, or Oscar Grant because he remembers one name from the early 21st century racial protests, then he’s talking about something that already happened combined with a ‘prediction’ that happens with sad regularity. The amount of specific knowledge that most people (not hobbiests or historians) have about a particular date far in the past is generally very scant and filled with incorrect information and misremembered years. No one today would think of Rodney King as contemporary with 2020 racial unrest since there’s a quarter centure gap, but it’s easy for us to think that anything happening from ‘first US president’ to ‘before the civil war’ as contemporary to each other even though that’s more than a half century. Just try it for 1980 (only 1/5 as long ago), if you try to write down a few facts about what happened that year to ‘prove’ that you’re from the future and then check with a little googling/wikiing, you’re likely to get some of them hilariously wrong, or to be ‘predicting’ something that already happened. Or getting names wrong like the above pandemic example - if you make a ‘prediction’ about AIDS being discovered in 1981, you’d be correct, but people in 1981 would think you were making stuff up because the term AIDS wasn’t actually invented until July of 1982 and not adopted by the CDC until September of that year. ---
**Author:** ![UltraVires](https://avatars.discourse-cdn.com/v4/letter/u/ecccb3/32.png) [@UltraVires](https://boards.straightdope.com/u/UltraVires)\ **Post date:** [June 7, 2020, 7:38pm UTC](https://boards.straightdope.com/t/if-you-could-travel-to-the-year-1820-how-could-you-prove-you-were-from-the-future/854931/175 "2020-06-07T19:38:15Z")
> [@eschereal](#): > > Well, you could travel to central NH and look for the venerable rock formation known as the “Old Man of the Mountain”. For your friends to fake that would be quite impressive. Or you could go to the much greater effort of traveling to the PNW to observe Mt St Helens in her ten-thousand-foot glory as a few of us remember – getting there, however, would probably pose a daunting challenge in 1820 that could well kill you or leave you totally exhausted and no longer interested in the overall exercise. > I think what I would do is the “easiest” endeavor: find a fairly competent craftsman who can help me build a [rogallo-style](https://en.wikipedia.org/wiki/Rogallo_wing) hang glider. Once you get a model that functions properly, even that relatively crude (by contemporary standards) design can perform impressively on a day that has good thermals. These are the things I object to as being good proof. If someone leads you out into the middle of the wilderness and shows you an impressive natural feature that nobody in the world at the time has heard of, are you going to think that this person has simply been there before or that they are a time traveler? ---
**Author:** ![Dewey\_Finn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dewey_finn/32/4222_2.png) [@Dewey\_Finn](https://boards.straightdope.com/u/Dewey_Finn)\ **Post date:** [June 7, 2020, 7:57pm UTC](https://boards.straightdope.com/t/if-you-could-travel-to-the-year-1820-how-could-you-prove-you-were-from-the-future/854931/176 "2020-06-07T19:57:42Z")
> [@eschereal](#): > > I think what I would do is the “easiest” endeavor: find a fairly competent craftsman who can help me build a [rogallo-style](https://en.wikipedia.org/wiki/Rogallo_wing) hang glider. Once you get a model that functions properly, even that relatively crude (by contemporary standards) design can perform impressively on a day that has good thermals. If you’re willing to go up in a hang glider built using 1820 technology, you’re a braver person than I am. Remember the level of medical care they had then, especially the lack of anesthesia. ---
**Author:** ![Quercus](https://avatars.discourse-cdn.com/v4/letter/q/7ab992/32.png) [@Quercus](https://boards.straightdope.com/u/Quercus)\ **Post date:** [June 7, 2020, 8:19pm UTC](https://boards.straightdope.com/t/if-you-could-travel-to-the-year-1820-how-could-you-prove-you-were-from-the-future/854931/177 "2020-06-07T20:19:09Z")
The more I learn about technological advances, the more I realize that they all depend on multiple other technologies (or economic circumstances) and that it almost never takes long for someone to come up with them once the circumstances are right. > [@eschereal](#): > > I think the hottest thing I would be capable of would be a refrigerator. I would not be able to actually make one myself, but in collaboration with a good tinkerer, I think we could get to the point of constructing a working ammonia absorption prototype that could be improved into a useful production design. If I could establish widespread simple refrigeration in 1820, it would be huge. My partner and I would become gazillionaires. What’s going to power the compressor? No electric engines, and no electric power anyway. So you’re certainly not building home refrigerators (which few people could afford anyway, given the cost of iron at that point) If metallurgy was up to the task, and you could get enough sufficiently pure ammonia, I suppose you could build a factory that produced ice. Whether you could do so more cheaply than someone just shipping ice from New England ([Ice trade - Wikipedia](https://en.wikipedia.org/wiki/Ice_trade#Opening_up_the_trade,_1800%E2%80%9330)), I’m not sure. Given that the basic theory of refrigeration was known by at least 1824 ([Carnot cycle - Wikipedia](https://en.wikipedia.org/wiki/Carnot_cycle)), and so all the necessary information was already available to 1820’s entrepreneurs, I suspect not. ---
**Author:** ![UltraVires](https://avatars.discourse-cdn.com/v4/letter/u/ecccb3/32.png) [@UltraVires](https://boards.straightdope.com/u/UltraVires)\ **Post date:** [June 7, 2020, 8:32pm UTC](https://boards.straightdope.com/t/if-you-could-travel-to-the-year-1820-how-could-you-prove-you-were-from-the-future/854931/178 "2020-06-07T20:32:53Z")
> [@Pantastic](#): > > Just try it for 1980 (only 1/5 as long ago), if you try to write down a few facts about what happened that year to ‘prove’ that you’re from the future and then check with a little googling/wikiing, you’re likely to get some of them hilariously wrong, or to be ‘predicting’ something that already happened. Or getting names wrong like the above pandemic example - if you make a ‘prediction’ about AIDS being discovered in 1981, you’d be correct, but people in 1981 would think you were making stuff up because the term AIDS wasn’t actually invented until July of 1982 and not adopted by the CDC until September of that year. I could start by saying that the US Hockey Team would win gold and beat the Russians in the Olympics, that Reagan would be elected President in the fall, and shortly after his inauguration he would be shot by a man named John Hinckley because he thought it would make actress Jodie Foster fall in love with him. Reagan would live, but his press secretary James Brady would be seriously wounded by a gunshot to the head. I could go on, but I think just that would have even the most skeptical people thinking I was a prophet, using black magic, or a time traveller. ---
**Author:** ![RivkahChaya](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rivkahchaya/32/8919_2.png) [@RivkahChaya](https://boards.straightdope.com/u/RivkahChaya)\ **Post date:** [June 7, 2020, 8:36pm UTC](https://boards.straightdope.com/t/if-you-could-travel-to-the-year-1820-how-could-you-prove-you-were-from-the-future/854931/179 "2020-06-07T20:36:37Z")
> [@UltraVires](#): > > I could start by saying that the US Hockey Team would win gold and beat the Russians in the Olympics, that Reagan would be elected President in the fall, and shortly after his inauguration he would be shot by a man named John Hinckley because he thought it would make actress Jodie Foster fall in love with him. Reagan would live, but his press secretary James Brady would be seriously wounded by a gunshot to the head. > > I could go on, but I think just that would have even the most skeptical people thinking I was a prophet, using black magic, or a time traveller. RE: Reagan getting shot-- you might get yourself arrested as a conspirator. Especially if you spelled Hinckley right. ---
**Author:** ![eschereal](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/eschereal/32/18939_2.png) [@eschereal](https://boards.straightdope.com/u/eschereal)\ **Post date:** [June 7, 2020, 9:19pm UTC](https://boards.straightdope.com/t/if-you-could-travel-to-the-year-1820-how-could-you-prove-you-were-from-the-future/854931/180 "2020-06-07T21:19:29Z")
> [@Quercus](#): > > What’s going to power the compressor? No electric engines, and no electric power anyway. So you’re certainly not building home refrigerators (which few people could afford anyway, given the cost of iron at that point) A flame. You could probably do it with a candle or two. Before Freon refrigerators, they used refrigerators that had no moving parts, and they were fairly popular. Simple fluids: hydrous ammonia boiled out of the water, run through cooling coils and fed into expansion tubes full of hydrogen where the ammonia would capture heat from the refrigeration box and then precipitate back into the solution where it would be boiled out for another cycle. The fluids would be reasonably obtainable in 1820 and the mechanism would be constructible by a metallurgist with better skills than I. Make a working model, refine it to decent performance and you suddenly have the thing that everyone wants. [Previous page](https://boards.straightdope.com/t/if-you-could-travel-to-the-year-1820-how-could-you-prove-you-were-from-the-future/854931.md?page=8) [Next page](https://boards.straightdope.com/t/if-you-could-travel-to-the-year-1820-how-could-you-prove-you-were-from-the-future/854931.md?page=10)