Two one: this is me reclaiming my title for the world's largest and tallest elephant, toothpaste, experiment - and this is a totally different kind of reaction. We discovered in all our experimentation called devil's toothpaste, which is insanely reactive and super dangerous. I'll explain why, in a minute, but for now here's a hint wow and if you look closely in bull shots, i'm not holding the trigger this. Kid is in fact, that kid was the whole reason we were there at all, because this was a culmination of eight months of planning to throw him the most epic birthday party ever and all of this started inadvertently from a single surprise phone call.

What's up flusher? Oh, my god, what's going on buddy, how are things man? They just got better. This is fletcher, and this is also fletcher a year before this call but unbeknownst to everyone at the time. Also pictured here under all that amazing hair was a fast-growing brain tumor. They eventually realized something was wrong and discovered.

It was a dangerous form of brain cancer, so rare he was only the sixth kid ever known to have had it so his family uprooted their lives for a year and moved almost a thousand miles to be closer to saint jude, where they removed the tumor and Would try and fix his brain? In fact, our call was the night before he was going back in for another brutal week of chemo he's such a funny kid, and i was so inspired by his hopeful attitude - that, after talking for an hour, i secretly vowed that if he made it to 13 Years old, i would fly him and his family out and surprise him with just the dopest birthday party ever and not long after i texted fletcher this picture, so he knew we had closely matching hairstyles. But what he didn't know is that plans were already underway for him and i to take back the record for the world's largest elephant toothpaste and as a quick refresher last summer, my buddy science bob, and i set the world record for elephant toothpaste by filling up An empty swimming pool i wanted to be able to swim in the foam afterwards, so we figured out how to use yeast as the catalyst which is in fact safer, but it doesn't react very fast and our video seemed to inspire some folks because two months later, This happened in david dobrik's backyard, where they didn't bother at the yeast and just took the normal reaction and scaled it up a bunch. But then, a few weeks later, these guys in brazil did the largest experiment yet and they are the current guinness world record holders. And so, even though fletcher's birthday was still eight months out, we started our testing right away because i knew blasting.

A world record amount of foam straight up into the sky wasn't as easy as it might sound, and the part that concerned me the most was picking the right, nozzle size and here's what i mean these three containers are identical, except for the diameter of their outlets. If that diameter is too large, it looks kind of cool, but it doesn't really go that high too small and it will go high, but it just looks like confetti and doesn't look that impressive, but for every container there is a goldilocks size diameter opening that gives You that cool laminator looking flow while still going pretty high, and you might think well why don't you just take a typical flask that works so well and just scale all the dimensions up, and we tried that on our first five foot scale test and just as I feared it went all confetti on us and the problem is illustrated here if you want to scale up and double all the dimensions of the block you get this as perfect. All these dimensions increased exactly by a factor of 2., but wait a sec. The volume increase by a factor of eight this is called the squared cube law, and its effects are everywhere in nature, such as putting a hard limit on just how big land animals can be, because how heavy you are is a function of your volume, but the Strength of your muscles and bones is a function of their cross-sectional area, so since animals evolved to get heavier by the power of three but stronger by only the power of two at some point, it's just too much so on the next five-foot test, we increase the Top diameter by a mere three and a half inches, but now the pendulum swung too far the other way, because, while the column looks smooth, it didn't really go that high and so finally, for the third test, we let the pendulum swing back.

Just a tad and shave down that diameter by just over an inch to try and dial in that goldilocks outlet, size and sure enough. The column went really high and looked great, but this test uncovered another issue. With such a high volume of foam, the pressure was creating some really high forces in the flask i mean that's a lot of damage which, quite frankly, left us with only one option, and so with the power flex tape. We scaled things up even further to a 10 foot test and did our best to interpolate that goldilocks outlet size.

So once again, the outlet size worked great, but our joint construction wasn't prepared for the further scaled up forces, in fact scory fat w for the flex tape where you could see it single-handedly held the thing together, even as the screws and wood busted through, and we Were realizing, we just had to make the structure so over engineered and indestructible, so the only option for the foam to escape the high pressure would be going out the top, and so, while that wasn't a perfect result, i felt like we'd learned enough from all of Our failures to design it strong enough for the final 20 foot world record version. In the end, we ran over 150 tests not only to determine the right scaled up, flask dimensions, but things like does neck length have an effect. What happens if you vary? The soap amounts, what effect do different brands of food coloring have. All of these tests were really insightful, but perhaps the most interesting finding was stumbling upon something i've affectionately named devil's toothpaste.

Now you might be thinking devil's toothpaste. That seems a bit extreme mark, but allow me to demonstrate this is a shoebox full of the standard formula of hydrogen peroxide, sodium iodide and soap that pretty much everyone uses to make elephant toothpaste. Now here's the same volume of reactants only this time using devil's toothpaste. Now see if you can spot the difference in real time, not only is it hyper-reactive, but the reaction is much hotter.

So you get these really cool bubble formations. Here's one more! Once again, this is normal. Elephant's toothpaste in an erlenmeyer flask, no big deal. People have been doing this for years, but once again, here's the same volume of reactants now only with devil's toothpaste given how explosive this is.

This may be irresponsible of me, but while we watch the replay i'll tell you exactly how to make it, you start with 2016 once that mixes you're gon na throw winfrey torch on the leftover, rabbit, fur and you're good to go, and so by taking some rigorous Safety precautions we also intended to set the first and therefore only world record for the world's largest devil's toothpaste experiment by filling six 55-gallon drums with 400 times the amount that broke the flask here, and so after 150 tests and eight months of work feeling much more Confident about our build plans and chemistry, we packed everything up and made our way to the small farming town of gridley california. We chose gridley because our family friend dale graciously agreed to let us use his land, which is full of hundreds of acres of walnut trees. Now, don't even think about it, fat gus. He also had a great backyard we could make use of, and so with only four days left till fletcher was flying out for the party.

We got to work on a 20-second, build montage and it took four consecutive 14-hour back-breaking days of labor in the hot sun, because with so much time to plan the most epic birthday party ever i just kept adding more and more ideas to the list. We would need to pull off so in addition to building the indestructible, 20-foot flask and the devil's toothpaste dumping mechanism, we also needed to make a methane bubble. Fountain, a 3d bubble printer, a fire tornado, a slip, n slide into a pool and an epic bubble pit, and even though i brought my buddies, it was cool to see this turn into a modern day. Small town, usa, barn racing.

If we needed extra hands or a piece of equipment, 10 neighbors were there like instantly to help us out, and so the morning of the big day, there was still a lot of last minute scrambling, but things were looking pretty good, i'm seriously so nervous right now. I love pranks and a surprise is like the most wholesome type of prank, so i haven't been able to sleep for days just thinking about this, like every last detail to how this will go down, and so with only one hour left. We did. One final test run on everything: first, the devil's toothpaste, a perfecto and then the 20-foot flask for the real reaction.

The peroxide would fill the whole bottom pool where john was standing and then the troughs would dump over all the catalyst at once sort of like this, and i should mention guinness only lets. You choose one world record category per vent, so we were going for the tallest, but when we did the math to scale up the flask to the arbitrary height i picked of 20 feet, and this is a true story. It was exactly one gallon less than the folks in brazil who set the world record for the largest, and so don't mind me. While i set these two gallon containers right here, and so as people started gathering for the surprise, i hit the hardened streets of gridley.

California, to look for some kind of last-minute disguise, and so after a bit of a warm-up, because these are all moves i can for sure do and that's definitely me in the costume the moment i had spent the last eight months planning for had finally arrived and The cover story for the kids is they were coming to tour a walnut farm of a distant relative and to provide a good juxtaposition. I wanted him to feel as awkward as possible for this part and then, when we gathered for the picture, i snuck up right behind him and took off my mask all right cool. What do you guys want to do next? What should we do? His sister isla also had no idea any of this was going to happen. What up buddy? How are you get in here? I'm the boy.

What's up dude when i'm not making videos, i'm the gridly, mascot mascot, to really stretch out the surprise. I wanted to think i was only there to drop in and say hi, so i had dale suggest that i take the kids for a ride in his dune buggy, to which i reluctantly agreed, because you know i'm a busy guy. I could do it like 15 minutes. You guys want to go for a razor ride.

Is that cool? Let's get the whole crew. Your sister, i had about like a half an hour, so it's good to meet you in real life. A single walnut grows in one of these, which is crazy to me all of those are just a single walnut. As we pulled up the driveway, i stopped the dune buggy in a precisely predetermined location, where the view of the 20-foot flask was obscured by the truck.

I heard it was your birthday, so i got you something simple. Well, tomorrow's, my real day, oh yeah, tomorrow, i'm one day off so fletch i've got ta uh, i got ta come clean, buddy. You and i today are gon na, set a guinness world record for the world's tallest elephant. Toothpaste, wait.

What are you kidding me? You are currently in a youtube video. I want you to wave your 20 million of your newest friends, hello, we're gon na put all the elephant toothpaste in there and just blast it in the air yeah. I got six minutes. I actually fully cleared my schedule with the surprise, fully and successfully executed.

My heart rate finally lowered a bit and i gave them a preview of all the cool stuff we had lined up for the party. Then we headed to the backyard where he saw the setup and his mom. You are devious because at this point it did sunk in that there would be no walnut farm tour and that her and i had been conspiring for months for now, though it was time to party my and everybody starts to move. Oh hey before we busted out the flaming bubbles or the bubble pit.

We headed across the street to check out the world's first and therefore largest devil's toothpaste, experiment. Three, oh my god, science bob came over and hooked us up with the slow-mo shot. Hmm, this shot was from a gopro on rails and we weren't quite fast enough with the pole and for some reason i found this like wall-e level pathetically sad you can see even in slo-mo, the reaction happened so incredibly fast and i apologize for the gratuitous amount Of slow-mo, but this has got to be the coolest thing i've ever filmed and afterwards it kept oozing. This rainbow play-doh extrusion thing.

It just looked like some kind of whimsical, alien landscape and, as you can see over time, it just sort of deflates itself. And after that we went back and ate some dinner and had some amazing and not at all creepy army of fletcher face cupcakes. While the crew started prepping for the big world record finale in the vein of cool stuff, i would need to have at my birthday party if i was turning 13 years old. I, of course, had to bust out the elon musk flamethrower to light some fire bubbles and finally was back to the front yard to top things off, with the most amazing bubble pit ever it was like belly flopping on a cloud, and at this point we realized It was taking way longer to fill up than we had calculated, so it was all hands on deck to try and pull this off before the sun went down.

Oh - and this is cool. The bubble pit was dual purpose because once emptied it served as the bunker to give a completely safe front row seat to whatever was about to happen, and so with the flask really close to being filled. Fletcher asked to take a very quick, last-minute ride in the tesla, because he'd never been in one inside this one. This is in like every video you guys are in a mark, grover video, for the request.

I gave them a quick ride. Remember our story. All right! 10 miles an hour tops, and so with the official measurement drone in the air. Our timing was perfect because we made it back just as they were sealing up the door for the big moment: okay fletcher, i'm handing this to you officially to think you should have been touring a walnut farm right now and so after eight months of planning and So much work by so many people, the coolest birthday present i've ever given anybody came down to this moment here we go three two one it worked.

It went look at my truck. Let's go! Oh my god. What do you guys think the bottom look at the truck it's like buried next to it, and i'd just like to point out how great that flowing column looks with a perfectly selected outlet diameter that is until things got chaotic, once the pressure changed drastically from the Big rupture, we literally made a rocket ship, i mean fundamentally, this is how rockets propel themselves an actual failure mode, wasn't really a floor strength issue as much as it was a stiffness issue. I knew our structure weighed over a ton, so i just didn't consider that the reaction could lift the whole thing five feet into the freaking air and in nasa that's what we refer to as a critical oversight.

But honestly, this result was way more spectacular, plus it leaves room for improvement, and i should also note, even with all that we still crushed the previous world record by more than double, and so, as the sun went down, science bob lit up the fire tornado as A fitting end to the party i also told fletcher, there was one more thing, which is that, with a little help from dale, he could use some heavy equipment to destroy our beautiful creation, and so with that, the party was all over i'll. Never forget this, oh as they drove away. I thought about everything they've been through for the past year and all the people that came together from all across the country to donate their time and energy for a kid. They've never even met, and i might not vote the exact same as all of them, but for like five inspiring days.

None of that stuff mattered. Whenever i find myself short on hope, i find it helps to put my phone down and choose to see the good parts in my fellow humans and be one of the good parts for my fellow humans to see and so to fletcher. Thank you for being such a good example of holding onto hope amidst really lame circumstances, happy birthday, buddy and congrats on your new world record. In the end, we used a chemical reaction to basically make a rocket ship now, if you want the same experience only without the eight months of prep work you're.

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And this also really does make for a great gift for any young person in your life. So thanks to kiwiko for being the best thanks to everyone who just made this the most epic birthday party ever and thanks to you for watching. If we can wrap up here, then we'll be able to go back. It's mr beast: what's up jimmy yeah, i'm filming it depends yeah.

Why are you asking me so many questions about elephant toothpaste.