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Please, don't try anything that you're about to see us do at home. Ever.

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In this episode of MythBusters...

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It's science!

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...the build team minds a myth from ancient China...

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as Carrie keeps an ear out for an invading army.

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I couldn't hear anything.

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And are we being fooled by the five-second rule?

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Oh, I picked it up after like three seconds. Would you eat it?

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Adam takes precautions in this bacteria bonanza.

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No French kissing.

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Adam.

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I don't eat my own food.

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Who are the MythBusters?

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Adam Savage.

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I reject your reality and substitute my own.

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And Jamie Heineman.

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We're either gonna die or we're gonna fly.

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Between them more than 30 years special effects experience.

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That was intense.

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They don't just tell the myths...

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they put them to the test.

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So, what's the myth? What do we got?

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This is Chinese invasion alarm.

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We got it from a high school science class which posts on our website.

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Apparently the Chinese had an early warning detection system for approaching armies...

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that involved stretching a leather membrane over the mouth of an 80-liter pottery jar.

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Then what they would do is strategically drill holes around the town...

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and lower these drums deep into these shafts.

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Men with the best hearing were stationed around these shafts...

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and they could listen to the vibrations.

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They could not only tell how far away the armies were...

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but from what direction they were coming from.

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Wow, it's kind of like an ancient rudimentary transducer, some kind.

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And it also sounds like something that we're all familiar with in old westerns.

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Keeping an ear to the ground perhaps refers to the fact that terra firma transmits sound waves.

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According to Hollywood at least, these can be detected by the highly-tuned ear.

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A French scouting party like it's not.

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With the gratuitous goat play behind them, they stumble into the pottery section...

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where, spoiled for choice, they take pot luck.

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How old are these? Could they be considered ancient?

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This one is almost 100 years old.

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100 years? Is this 100 years old?

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Yeah, that's antique.

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Oh, wow.

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Stickers newer though.

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That face itself could be 100 years old.

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That's a good start. What are these made out of?

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They're made by, you know, clay or ceramic.

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Ceramic, okay.

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It's a very good one.

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This is the bit where they ask the shop owner if she's heard of the myth...

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that they used to use these pots, they would bury them in the ground and cover them with leather skins.

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And this is the bit where the shopkeeper says...

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No, I didn't hear about that.

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Do you think it would work?

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I have no idea because I haven't tried it before.

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Can't say fairer than that.

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Armed with a variety of pots, they head for home.

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Taxi!

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Back at M5, Grant and Carrie join forces to turn their pots into drums.

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Jammin'.

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The number of drums they've made between them amounts to less than one.

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So they decide to pool their ignorance.

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Apologies to everyone who actually makes their own drums.

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We have no idea what we're doing.

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Meanwhile, Tauri's marching to his own beat...

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by building mechanical boots to simulate an advancing army.

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I think that's gonna work pretty good.

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Grant and Carrie have slipped into a workman-like rhythm...

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and the first drum looks relatively professional.

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Tauri's impressed.

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Look at our little drum, Tauri.

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Doesn't this look cool?

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Wow, you guys are like regular drum makers.

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How'd you learn how to make the...

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...fake it, just like everything we do.

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Everything's running smoothly.

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The build team is operating like a well-oiled machine.

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What could possibly go wrong?

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After the break...

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I love having bacteriological tests done.

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Adam and Jamie count colonies in their bacterial empire.

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Oh, I got something in my eye.

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And Carrie gets to shave a goat for science.

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You know, my people come from a long line of goat shavers.

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Well, I believe you're about to tell us...

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a classic American old wives tale.

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Absolutely. Having kids, I'm really familiar with this.

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It's the five-second rule.

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And the rule is, if you drop a piece of food on the floor...

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and retrieve it within five seconds...

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it won't have actually gathered any bacteria...

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or viruses from the floor, and it's okay to eat it.

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And really, it's a very good thing.

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I think it's a good thing.

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I think it's a good thing.

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And really, it's almost always...

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you have to say, five-second rule,

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before you pop that cookie in your mouth.

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Or that toast.

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In an earlier myth, the team was testing whether toast...

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really does drop butterside down.

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Yes. You're gonna eat those.

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A hungry Scotty invoked the five-second rule.

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What's that rule?

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That if you drop something on the floor...

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and it's within five seconds that you pick it up,

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you can still eat it.

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Some viewers may wish to look away...

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as Scotty eats toast that's been on the sidewalk.

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Yes!

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Okay, I'm gonna say, oh, I want...

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well, I guess I won't say that.

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So was Scotty safe to snack?

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Or did she ingest a battalion of bacteria?

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Oh, I picked it up after like three seconds.

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Would you eat it?

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But I wouldn't eat it just because you've handled it.

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To make things easier, we've gotten some contact plates...

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which have a growth medium inside them...

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that can grow either bacteria or fungi...

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which can produce really harmful toxins.

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And the first thing we're gonna do is take those...

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and see what the distribution of fungi and bacteria is...

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on your kitchen floor.

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Before they drop the food,

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they need to know the bacteria distribution on Jamie's floor.

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So is M5 as neat and clean as a new pin?

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Or is it a filth-ridden bucket of scum?

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Adam and Jeremy don't want to contaminate their samples.

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So they don gloves and masks.

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In line with the myth,

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each contact plate will get five seconds exposure...

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to different sections of floor.

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So I'm gonna grab one of these plates here.

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And in here, we're gonna test in front of the sink...

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and in front of the fridge.

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Okay.

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The contact plates contain a tryptic soy medium...

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which may sound like a vegan psychic...

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but is actually a substance that encourages the growth of bacteria.

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Can you tell me when to go?

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Go.

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If the floor is contaminated,

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the contact plates will show it.

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Four... five. Four... five.

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Once they've swabbed the kitchen's decks,

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they head for the Mythbusters mess hall.

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Okay, ready.

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Then it's downstairs to the shop floor.

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You know, now we get to find out definitively...

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just how clean your shop is.

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It's a shop. What do you want?

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I want to be able to eat off the damn floor.

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What's my immune system for anyway?

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Four... five.

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Right. Bathroom.

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Over the years, the Mythbusters bathroom has played host...

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to some less-than-hygienic hijinks.

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It's housed ducks and skunks...

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and been rubbed down with engine grease.

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This place looks a little dingy, Jimmy.

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Yeah, this may well be the dirtiest part of the shop, huh?

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I just want to do one brush for my own personal edification...

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right on the toilet seat,

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because I've heard a myth that the toilet seat's actually the cleanest place...

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in any given house.

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Good. Four... five.

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That's why I love this job.

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All right, you ready to incubate these guys?

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All right.

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They'll incubate the plates for 24 hours at 98.6 degrees Fahrenheit.

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Otherwise known as body temperature.

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Shop floor.

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Lunch table. Kitchen sink.

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And my personal favorite, the toilet seat.

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Early indications suggest that M5 may be a little workshop of horrors.

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The build team is testing the myth that ancient Chinese cities...

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used pottery drums to listen out for approaching armies.

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Tari's been working on a marching machine,

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while Kari and Grant have been having a bash at making drums.

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Everything's been going smoothly, which is a pity,

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as they learn that they've been barking up the wrong myth.

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We just received some new information about this story...

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that's going to radically change the direction that we're going to have to take.

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And, you know, what happened was the publishers of the textbook...

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that was the source of the original story,

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have sent us their fact-checking sheets.

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Their source for this story comes from a book, Mount Zu,

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which is about four-century BC.

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The shafts were five paces apart.

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They were 15 feet below the base of the city wall.

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We found out the size of the pottery jars were 40 toe,

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which is equivalent to 200 liters.

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I mean, that's a little bigger than we had thought before.

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The most significant thing of all is the fact that this was to detect...

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the tunneling and mining of a besieging army...

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and not an approaching marching one.

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The history of warfare is shot through with examples of military tunnels,

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as this documentary film from the First World War shows.

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Below the ground, the tunnelers are at work on mines under the enemy positions.

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Listening for their sapping suggests that enemy countermining is close.

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Borrowing armies monitored each other's movements...

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by listening out for the sounds of nearby digging.

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When this is confirmed, work must be hurried.

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Galleries beneath the enemy positions were packed with explosives,

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then detonated.

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According to the myth, the ancient Chinese also used military tunnels.

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Ah, well, that makes so much more sense.

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I was trying to wrap my head around why you could use these embedded drums in shafts

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to detect an oncoming army when you could use watchtowers and signal fires

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to do it at the speed of light instead of the speed of sound.

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That sounds like it makes our experiment a lot easier.

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The new research reveals that the myth originated with Mo Tzu,

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a philosopher who was writing about 400 BC.

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He described an early warning system designed to protect walled cities against tunneling invaders.

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It comprised a system of sunken drums,

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which could pick up vibrations from underground digging.

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By comparing the intensity of the sound at different locations,

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centuries could determine the direction of an incoming tunnel and intercept it.

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To get this myth back on track,

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Carrie and Tori take another pot shot at another pot shop to find a 200-liter vessel.

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Ooh, God, this one's pretty. Look at that glaze.

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Oh, I love these. They're so cute.

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I'm so happy. Look at that.

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Tori leaves the browsing to Carrie and gets down to the business at hand.

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Okay, what do you got for height?

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58 inches.

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504. That's about...

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That's too much. 41 inches.

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41? Exactly 200 liters.

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I think we found our pot.

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They've got their pot, so it's back to M5 to shave a goat.

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No kidding. Really.

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You know, my people come from a long line of goat shavers, so I feel it's in my blood.

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Apparently, goat skins for the fuller drum only come covered in hair,

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which presents Carrie with yet another opportunity for growth.

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I can't say I'm necessarily looking forward to shaving the goat,

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but I am looking forward to calling my parents tonight and be like,

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Guess what I did today?

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Carrie's never shaved a goat, but she's incredibly well connected,

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proving that it's not what you know, it's who you know.

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We talked to Akbar the goat shaver,

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and what he recommended is to first take clippers,

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then stretch it after it's been soaked for half an hour,

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and then take one of those little disposable razors so that you can get the fine stubble.

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In the world of goat shaving, Akbar is king.

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Carrie follows his instructions to the letter with royal results.

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Excellent job shaving your goat.

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The skin is soaked in water so that it's ready for stretching.

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Then placed over the mouth of the 200-liter pot.

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With a morning's practice under their belts,

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Carrie and Grant make light work of stringing the drum.

254
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When the skin is taught, they give it one final shave.

255
00:13:37,000 --> 00:13:39,000
Shaving the drum skin.

256
00:13:41,000 --> 00:13:44,000
Coming up, Mythbusters takes microbiology 101.

257
00:13:44,000 --> 00:13:48,000
Would only a fool use the five-second rule?

258
00:13:48,000 --> 00:13:50,000
Don't try this at home.

259
00:13:51,000 --> 00:13:55,000
And the built-in goes underground in Chinese invasion alarm.

260
00:13:55,000 --> 00:13:57,000
Let's do some exploring.

261
00:14:05,000 --> 00:14:11,000
According to the five-second rule, food that has been on the floor for five seconds or less will be uncontaminated.

262
00:14:11,000 --> 00:14:12,000
Good.

263
00:14:12,000 --> 00:14:20,000
To test the myth, Adam and Jamie have placed bacteria contact plates on different parts of M5's floor for five seconds of peats.

264
00:14:22,000 --> 00:14:26,000
The plates have been incubating for 24 hours at body temperature

265
00:14:26,000 --> 00:14:29,000
to see just how much bacteria they've picked up.

266
00:14:30,000 --> 00:14:31,000
Let's scoop them up.

267
00:14:31,000 --> 00:14:32,000
Ooh.

268
00:14:32,000 --> 00:14:34,000
They're all kind of yummy, aren't they?

269
00:14:34,000 --> 00:14:37,000
Oh man, this stuff is rigged.

270
00:14:37,000 --> 00:14:38,000
Yep.

271
00:14:38,000 --> 00:14:44,000
To discover M5's level of hygiene, the guys count the number of bacteria colonies on each sample.

272
00:14:44,000 --> 00:14:47,000
The bathroom of the two looks like a bloody horror shot.

273
00:14:47,000 --> 00:14:51,000
I think I dropped it right in someone's drop of whee or something.

274
00:14:51,000 --> 00:14:54,000
Shop floor number two, 132.

275
00:14:54,000 --> 00:14:56,000
Lunch table number two?

276
00:14:56,000 --> 00:14:57,000
Yeah.

277
00:14:57,000 --> 00:14:58,000
26 colonies.

278
00:14:58,000 --> 00:15:01,000
Adam's like a kid with a new chemistry set.

279
00:15:01,000 --> 00:15:04,000
I love having bacteriological tests done.

280
00:15:04,000 --> 00:15:08,000
Come to think of it, Adam is a kid with a new chemistry set.

281
00:15:08,000 --> 00:15:15,000
Later on, I want to lick one of these and get a dog to lick one and see if my mouth is cleaner than a dog's mouth.

282
00:15:15,000 --> 00:15:19,000
How are you going to feel if it turns out your mouth is dirtier than a dog's?

283
00:15:19,000 --> 00:15:20,000
That's fine.

284
00:15:20,000 --> 00:15:22,000
It's served me just fine until now.

285
00:15:22,000 --> 00:15:23,000
There's no reason to freak out.

286
00:15:23,000 --> 00:15:29,000
Adam's busting to check the results of the toilet seat myth, and it's a Eureka moment.

287
00:15:29,000 --> 00:15:30,000
Whoa!

288
00:15:30,000 --> 00:15:34,000
There is no, almost no bacteria on the toilet seat.

289
00:15:34,000 --> 00:15:37,000
That is so cool.

290
00:15:37,000 --> 00:15:40,000
We have proven a myth.

291
00:15:40,000 --> 00:15:49,000
Looking at our samples just briefly from all over MythBusters, your toilet seat seems to be the most bacteria free.

292
00:15:49,000 --> 00:15:55,000
Well, you know, that doesn't really surprise me a whole lot because we're testing the floor, you know?

293
00:15:55,000 --> 00:15:59,000
But people don't rub their bare bottoms on your floor all the time.

294
00:15:59,000 --> 00:16:07,000
I mean, you know, I'm thinking, this is everyone in the company, but has sat where I put this peature dish.

295
00:16:07,000 --> 00:16:13,000
If cleanliness is next to godliness, then heaven is on MythBusters' toilet seat.

296
00:16:13,000 --> 00:16:16,000
Toilet humor aside, what did the floor test show?

297
00:16:16,000 --> 00:16:23,000
On all of these figures, there's sometimes a very wide variability between two spots we chose that were side by side.

298
00:16:23,000 --> 00:16:30,000
I mean, we might not end up testing the five-second rule here, we might end up testing where you happen to drop the piece of food.

299
00:16:30,000 --> 00:16:43,000
What we need to do is to start with a sterile surface and evenly contaminate it so that we have an even playing field and that will boil it down to the time, not the actual surface or what's on it.

300
00:16:43,000 --> 00:16:47,000
Right, so cleanly bacterial...

301
00:16:47,000 --> 00:16:50,000
Right, that sounds great.

302
00:16:51,000 --> 00:17:00,000
In the myth of the five-second rule, Adam and Jamie have decided to make a uniformly filthy piece of floor.

303
00:17:00,000 --> 00:17:05,000
That way, when they drop food on it, they should get consistent contamination.

304
00:17:05,000 --> 00:17:07,000
I see some pans.

305
00:17:07,000 --> 00:17:09,000
We have some tiles.

306
00:17:09,000 --> 00:17:11,000
We have floor tiles.

307
00:17:11,000 --> 00:17:13,000
We have beef broth.

308
00:17:13,000 --> 00:17:16,000
And we have some pans.

309
00:17:16,000 --> 00:17:20,000
For some reason, whenever I see the pans, I have the desire to smash them on my head.

310
00:17:20,000 --> 00:17:21,000
You ready?

311
00:17:21,000 --> 00:17:22,000
Yeah.

312
00:17:22,000 --> 00:17:23,000
See if I can get a perfect face print.

313
00:17:23,000 --> 00:17:26,000
So with that out of the way, what's the plan?

314
00:17:26,000 --> 00:17:33,000
So the plan is that once we get these trimmed down to fit in the pans, we're going to pour beef broth.

315
00:17:33,000 --> 00:17:35,000
What's beef broth?

316
00:17:35,000 --> 00:17:37,000
Is it beef broth?

317
00:17:37,000 --> 00:17:48,000
They leave the floor tiles to rot in the big boy and Adam turns his attention to another mini myth.

318
00:17:48,000 --> 00:17:54,000
I've always heard that a dog's mouth is supposedly cleaner than a human's mouth.

319
00:17:54,000 --> 00:17:57,000
So this has got nothing to do with the five-second rule.

320
00:17:57,000 --> 00:18:00,000
We're just comparing your hygiene to a dog's, right?

321
00:18:00,000 --> 00:18:01,000
Not my hygiene.

322
00:18:01,000 --> 00:18:05,000
A human's hygiene in their mouth to a dog's hygiene.

323
00:18:05,000 --> 00:18:11,000
I guess empirically what we will be testing is my hygiene against Linda's dog, but...

324
00:18:11,000 --> 00:18:15,000
Just do it. Just look at the darn thing.

325
00:18:15,000 --> 00:18:17,000
All right. Here we go. First science.

326
00:18:17,000 --> 00:18:19,000
Ew!

327
00:18:21,000 --> 00:18:23,000
Doesn't taste like anything.

328
00:18:23,000 --> 00:18:24,000
Where's the dog?

329
00:18:24,000 --> 00:18:26,000
Bring on the dog!

330
00:18:27,000 --> 00:18:30,000
Want to lick the sterile agar plate?

331
00:18:30,000 --> 00:18:34,000
Oh, Lou, that's perfect. Thank you. Good girl.

332
00:18:34,000 --> 00:18:39,000
Is it just me or does Lulu look quietly confident? Time will tell.

333
00:18:39,000 --> 00:18:44,000
Back at the myth of the five-second rule, the floor tiles are fully festered.

334
00:18:44,000 --> 00:18:45,000
What, five days now?

335
00:18:45,000 --> 00:18:47,000
They smell really, really bad.

336
00:18:47,000 --> 00:18:53,000
Yeah, I know. Let's get them out, hang them up and dry them off and see if we can use them today.

337
00:18:57,000 --> 00:19:02,000
Jamie punches out plastic templates which will ensure sample sizes are consistent.

338
00:19:03,000 --> 00:19:07,000
While they're sterilizing in the microwave, Adam gloves up.

339
00:19:07,000 --> 00:19:11,000
Coming up, MythBusters takes microbiology 101.

340
00:19:13,000 --> 00:19:17,000
Adam has to behave like this. It's in his contract.

341
00:19:17,000 --> 00:19:20,000
But whatever you do, don't do this at home.

342
00:19:20,000 --> 00:19:28,000
To test the five-second rule, they'll use a wet food, a dry food, and an evenly contaminated floor tile.

343
00:19:28,000 --> 00:19:29,000
So?

344
00:19:29,000 --> 00:19:30,000
It's science!

345
00:19:30,000 --> 00:19:36,000
Samples of wet pastrami and dry crackers are exposed for two seconds and six seconds.

346
00:19:36,000 --> 00:19:40,000
In other words, for less than and more than five seconds.

347
00:19:40,000 --> 00:19:47,000
They also do a control on samples that don't touch the floor at all, in case they are already coated with bacteria.

348
00:19:47,000 --> 00:19:49,000
Control number two.

349
00:19:49,000 --> 00:19:54,000
I know I love building big things and blowing stuff up, but this is also super, super fun.

350
00:19:54,000 --> 00:19:56,000
Okay, fishing out a new one?

351
00:19:56,000 --> 00:19:57,000
He doesn't care.

352
00:19:57,000 --> 00:19:58,000
And go.

353
00:20:06,000 --> 00:20:10,000
And the bulk of our MythBusters bacteriologic test is done.

354
00:20:10,000 --> 00:20:11,000
Cool.

355
00:20:20,000 --> 00:20:22,000
Can't wait to find out what happens.

356
00:20:28,000 --> 00:20:34,000
In the myth of the Chinese invasion alarm, Carrie takes a step back in time

357
00:20:34,000 --> 00:20:39,000
to abandon 19th century gold diggings in the hills beyond San Francisco.

358
00:20:39,000 --> 00:20:44,000
Frank Jacobi leads Carrie through the dark passageways of the Priest Mine,

359
00:20:44,000 --> 00:20:47,000
one of the oldest hard rock mines in California.

360
00:20:47,000 --> 00:20:50,000
The walls are etched with history.

361
00:20:50,000 --> 00:20:56,000
Like the mythical tunnels of the Chinese invasion alarm, the Priest Mine was dug by hand.

362
00:20:56,000 --> 00:20:59,000
One of the things that is a surprise in here is what you're leaning against.

363
00:20:59,000 --> 00:21:01,000
Take a good close look at the walls there.

364
00:21:01,000 --> 00:21:03,000
And what do you see on those walls?

365
00:21:03,000 --> 00:21:04,000
Looks like Freddy Krueger was in here.

366
00:21:04,000 --> 00:21:09,000
What those are, those are the miners' tool marks that they used to carve out this tunnel.

367
00:21:09,000 --> 00:21:13,000
Those are the chisel and pick marks from 150-plus years ago.

368
00:21:13,000 --> 00:21:20,000
This is as close as they're going to get to an ancient Chinese military tunnel in modern California.

369
00:21:20,000 --> 00:21:25,000
Now they have to find a location where they can simulate the sound of an underground army.

370
00:21:25,000 --> 00:21:32,000
And then up here is the air shaft going up to the surface about 55 feet to the top, to the wooden roof up there.

371
00:21:32,000 --> 00:21:38,000
This place is beautiful. I'm thinking for our criteria, we need two things.

372
00:21:38,000 --> 00:21:44,000
We need very specifically a 15-foot shaft that has a floor at the bottom and an open mine.

373
00:21:44,000 --> 00:21:48,000
The Priest Mine perfectly fulfills one criteria.

374
00:21:48,000 --> 00:21:54,000
So they resurface to look for a nearby spot where they can sink their early warning hole.

375
00:21:54,000 --> 00:21:56,000
I think this might be where we need to dig the hole.

376
00:21:56,000 --> 00:22:01,000
If we can get a backhoe up here and we're this close to a mine, I don't think we're going to get anything more ideal.

377
00:22:01,000 --> 00:22:03,000
Okay, after the break.

378
00:22:03,000 --> 00:22:05,000
This is insane.

379
00:22:05,000 --> 00:22:06,000
They got it, they got it.

380
00:22:06,000 --> 00:22:11,000
The build team avoids backache in the myth of the Chinese invasion alert.

381
00:22:11,000 --> 00:22:18,000
If Carrie, Grant and I were to try to dig this hole, I don't know how long it would take, maybe a week.

382
00:22:24,000 --> 00:22:33,000
In the myth of the Chinese invasion alarm, the build team has been laying the foundations for a foray into the world of ancient underground warfare.

383
00:22:33,000 --> 00:22:38,000
The tightest tap, I think is going to work great.

384
00:22:38,000 --> 00:22:45,000
They're investigating the myth that ancient Chinese cities had a detection system for tunneling invaders.

385
00:22:46,000 --> 00:22:49,000
It's all about seismology.

386
00:22:49,000 --> 00:22:57,000
Rocks, as hard as they seem, are elastic and deform when impacted by force, like in an earthquake.

387
00:22:57,000 --> 00:23:05,000
Today, scientists can pick up seismic waves from even the smallest underground tremors using geophones.

388
00:23:05,000 --> 00:23:11,000
Replace tremors with a tunneling army and the geophones with drums and you've got yourself a myth.

389
00:23:15,000 --> 00:23:23,000
The build team has borrowed some geophones from the U.S. Geological Survey, which they plan to use as controls during their experiment.

390
00:23:23,000 --> 00:23:28,000
But, as ever, Grant tests them out in the lot of M5.

391
00:23:28,000 --> 00:23:29,000
Go get them, boy.

392
00:23:29,000 --> 00:23:35,000
He's aided by his very own homemade robot, which comes equipped with a handy pickaxe.

393
00:23:35,000 --> 00:23:40,000
The tiny seismic waves are detected by the geophone and displayed on a monitor.

394
00:23:41,000 --> 00:23:50,000
Meanwhile, Tari is constructing a metal and ply gantry, which they'll place over their shaft for safety.

395
00:23:50,000 --> 00:23:53,000
The plan's simple.

396
00:23:53,000 --> 00:23:56,000
Sink a 15-foot shaft and lower in the drum.

397
00:23:56,000 --> 00:24:04,000
30 feet away, in the priest's mind's air shaft, they'll swing their pick and see if the vibrations are detectable.

398
00:24:04,000 --> 00:24:05,000
They're good to go.

399
00:24:05,000 --> 00:24:10,000
Time to load up the Mythbusters mule and head for them their hills.

400
00:24:13,000 --> 00:24:18,000
On second thoughts, they dump the mule and the shovels and bring in a digger.

401
00:24:18,000 --> 00:24:21,000
Ever heard of taking a hammer to crack a nut?

402
00:24:21,000 --> 00:24:23,000
This is insane.

403
00:24:23,000 --> 00:24:25,000
I got it, I got it.

404
00:24:29,000 --> 00:24:38,000
While the build team supervises the city's defenses, Adam and Jamie head below to the mine, which will represent the besieging tunnel.

405
00:24:38,000 --> 00:24:40,000
I don't think I've ever been in the mine before.

406
00:24:40,000 --> 00:24:43,000
Well, then you're just about to have a real neat experience.

407
00:24:43,000 --> 00:24:48,000
Jamie actually used to do silver mining back in the 30s in South America, didn't you?

408
00:24:49,000 --> 00:24:54,000
Well, I noticed this picky has on his shoulder here. I'm watching out for him.

409
00:24:54,000 --> 00:24:56,000
Shall we go on in?

410
00:24:56,000 --> 00:25:01,000
To test the myth, they're looking for three locations where their invading army can go to work.

411
00:25:01,000 --> 00:25:04,000
They couldn't have hoped for anything more authentic.

412
00:25:04,000 --> 00:25:09,000
You can pretty much match up the same pick you have to what you'll see on the wall here.

413
00:25:09,000 --> 00:25:14,000
This was all pretty much dug by hand. It's the same kind of idea.

414
00:25:14,000 --> 00:25:16,000
Wow.

415
00:25:16,000 --> 00:25:21,000
Now imagine doing that 12 hours a day, day in and day out, seven days a week. No days off.

416
00:25:21,000 --> 00:25:23,000
A lot of work.

417
00:25:23,000 --> 00:25:24,000
Good exercise.

418
00:25:24,000 --> 00:25:25,000
You betcha.

419
00:25:25,000 --> 00:25:32,000
Having seen the mine firsthand, the guys take a look at a map to determine exactly where Jamie will launch his assault.

420
00:25:32,000 --> 00:25:35,000
So this is the map that you were talking about?

421
00:25:35,000 --> 00:25:37,000
Yeah, this kind of lays it all out for you.

422
00:25:37,000 --> 00:25:39,000
And what are we right here?

423
00:25:39,000 --> 00:25:42,000
That's correct. That's the entrance to the priest mine.

424
00:25:42,000 --> 00:25:45,000
So that's that little offside room that was one of our sites, right?

425
00:25:45,000 --> 00:25:46,000
That's right.

426
00:25:46,000 --> 00:25:49,000
And that's the shaft where the other site was.

427
00:25:49,000 --> 00:25:50,000
That's right.

428
00:25:50,000 --> 00:25:52,000
So this goes up to the surface right about here.

429
00:25:52,000 --> 00:25:57,000
Our holes probably, our alarm hole is probably right here.

430
00:25:57,000 --> 00:26:06,000
I'd say we look at three sites. I'd say it's that one, this one, and then this one would be the last site that we'd try if neither of these worked.

431
00:26:06,000 --> 00:26:11,000
Sure. Meanwhile, 50 feet above, the chain gang has never had it so good.

432
00:26:11,000 --> 00:26:16,000
Now I'm excited. I can't believe how easy it was to do all this.

433
00:26:16,000 --> 00:26:18,000
Or have somebody else do all this.

434
00:26:18,000 --> 00:26:19,000
Yeah.

435
00:26:19,000 --> 00:26:24,000
Busting ancient myths with modern equipment sits just fine with Tarry.

436
00:26:24,000 --> 00:26:28,000
I mean, this is taking maybe like an hour to dig this hole.

437
00:26:28,000 --> 00:26:34,000
If Carrie, Grant, and I were to try to dig this hole, I don't know how long it would take. Maybe a week.

438
00:26:34,000 --> 00:26:39,000
In no time at all, the digger's done digging, and the built-in checks the depth.

439
00:26:39,000 --> 00:26:40,000
At 16 feet.

440
00:26:40,000 --> 00:26:42,000
All right. We made it.

441
00:26:42,000 --> 00:26:43,000
Yay!

442
00:26:43,000 --> 00:26:44,000
Nice job.

443
00:26:44,000 --> 00:26:45,000
Awesome.

444
00:26:45,000 --> 00:26:46,000
Woo!

445
00:26:46,000 --> 00:26:47,000
So far so good.

446
00:26:47,000 --> 00:26:48,000
Awesome.

447
00:26:48,000 --> 00:26:51,000
Then Grant spots a possible spanner in the earthworks.

448
00:26:51,000 --> 00:27:02,000
It's a wet spot on the side of the hole, and that could mean that come tomorrow morning when we come back out here, the hole will be filled with water.

449
00:27:02,000 --> 00:27:08,000
The build team wraps up the day by installing Tarry's homemade safety gantry.

450
00:27:08,000 --> 00:27:10,000
Well, watch yourself, Carrie.

451
00:27:10,000 --> 00:27:11,000
Yeah.

452
00:27:11,000 --> 00:27:14,000
You are almost lost, Carrie.

453
00:27:14,000 --> 00:27:19,000
Tomorrow we'll tell if they have an alarm hole or a bore hole on their hands.

454
00:27:24,000 --> 00:27:29,000
After the break, is Adam's mouth dirtier than a dog's?

455
00:27:29,000 --> 00:27:31,000
I don't eat my own poo.

456
00:27:31,000 --> 00:27:34,000
And will the five-second rule bite the dust?

457
00:27:34,000 --> 00:27:41,000
In another 24 hours, we're going to know the answer to the age-old question of the five-second rule.

458
00:27:47,000 --> 00:27:53,000
At the M5 laboratory, Adam and Jamie are testing the five-second rule on food samples.

459
00:27:53,000 --> 00:27:58,000
While they wait for their samples to incubate, they check out a related myth.

460
00:27:58,000 --> 00:28:00,000
Let's see the dogs move along.

461
00:28:05,000 --> 00:28:08,000
Well, that's clear enough.

462
00:28:08,000 --> 00:28:11,000
That looks pretty definitive. That's my mouth.

463
00:28:11,000 --> 00:28:17,000
I can see tons of little bacteria and colonies growing in exactly the shape of my tongue.

464
00:28:17,000 --> 00:28:22,000
And here, where Lulu licked, I see a much smaller concentration.

465
00:28:22,000 --> 00:28:25,000
So no French kissing dogs, I think, is our conclusion here.

466
00:28:25,000 --> 00:28:28,000
I would be more inclined to say no French kissing Adam.

467
00:28:28,000 --> 00:28:33,000
And you know, my mouth isn't representative of sample. I don't eat my own poo.

468
00:28:33,000 --> 00:28:35,000
Let's take that as rare.

469
00:28:35,000 --> 00:28:41,000
Nonetheless, if bacteria count as your benchmark, you've got to smooch the punch.

470
00:28:41,000 --> 00:28:45,000
Bacteria myths are being busted by the bucket full.

471
00:28:45,000 --> 00:28:47,000
But how about the big one?

472
00:28:47,000 --> 00:28:51,000
The meat and cracker samples are fully incubated and ready to be counted.

473
00:28:51,000 --> 00:28:55,000
So this is supposed to be our definitive test of the five-second rule.

474
00:28:55,000 --> 00:28:57,000
What do you think is actually going to happen?

475
00:28:57,000 --> 00:28:59,000
I don't think there's going to be any significant difference.

476
00:28:59,000 --> 00:29:04,000
I tend to agree with you that there's not going to be a significant difference between two seconds and six seconds.

477
00:29:04,000 --> 00:29:07,000
But shall we start counting?

478
00:29:07,000 --> 00:29:12,000
The results show that all the food did pick up bacteria from the floor top.

479
00:29:12,000 --> 00:29:15,000
21 for cracker, two seconds.

480
00:29:15,000 --> 00:29:19,000
But the wet pastrami picked up more than the dry crackers.

481
00:29:19,000 --> 00:29:21,000
322 for meat, six seconds.

482
00:29:21,000 --> 00:29:26,000
On the crucial question of time, the results were less than definitive,

483
00:29:26,000 --> 00:29:31,000
with no conclusive distinctions between the two-second and the six-second samples.

484
00:29:31,000 --> 00:29:37,000
So does that mean that it's better to eat crackers that have been dropped on the floor than pastrami that's been dropped on the floor?

485
00:29:37,000 --> 00:29:44,000
Well, not exactly, but it does mean that if there is something harmful there on the floor, the odds are the pastrami is more likely to pick it up.

486
00:29:44,000 --> 00:29:46,000
But what about the five-second rule?

487
00:29:46,000 --> 00:29:50,000
Was there a difference between the samples dropped for two seconds and the samples dropped for six seconds?

488
00:29:50,000 --> 00:29:53,000
Well, I don't think the results were all that conclusive.

489
00:29:53,000 --> 00:30:03,000
But as far as I can tell, time didn't seem to be a factor because all the samples seemed to show about the same amount of contamination no matter how long they sat on the floor.

490
00:30:03,000 --> 00:30:06,000
But I'm not ready to put this one to rest just yet.

491
00:30:06,000 --> 00:30:09,000
I think we have one more test to do.

492
00:30:09,000 --> 00:30:12,000
It's not really about the food and it's not really about the floor.

493
00:30:12,000 --> 00:30:13,000
It's about the time.

494
00:30:13,000 --> 00:30:21,000
And I'd like to eliminate the food and try applying our contact plates directly to our inoculated floor surface for the correct periods of time.

495
00:30:21,000 --> 00:30:26,000
Two seconds, six seconds, and see if there's any difference in how much bacteria they pick up.

496
00:30:26,000 --> 00:30:30,000
I think that makes sense. It's removing all the other variables.

497
00:30:30,000 --> 00:30:36,000
The five-second rule has been around a long time and it's not giving up without a fight.

498
00:30:36,000 --> 00:30:44,000
By leaving out the food in this final test, they eliminate every variable except the crucial one, time.

499
00:30:44,000 --> 00:30:49,000
Well, in another 24 hours we're going to know the answer to the age-old question.

500
00:30:50,000 --> 00:30:52,000
Of the five-second rule.

501
00:30:52,000 --> 00:30:54,000
Load me up.

502
00:30:54,000 --> 00:30:57,000
24 hours later, it's time to count the colonies.

503
00:30:57,000 --> 00:31:05,000
If there's any truth to the five-second rule, the two-second plates should have far less bacteria than the six-second ones.

504
00:31:05,000 --> 00:31:07,000
Wow, that's a...

505
00:31:07,000 --> 00:31:08,000
Dude.

506
00:31:08,000 --> 00:31:10,000
Two-second exposure is huge.

507
00:31:10,000 --> 00:31:17,000
The colony count is so massive as to be uncountable, but it looks identical for both.

508
00:31:17,000 --> 00:31:23,000
There's no discernible difference between the samples, regardless of how long they spent on the floor.

509
00:31:23,000 --> 00:31:25,000
This is really the definitive test for this myth.

510
00:31:25,000 --> 00:31:32,000
We could test a million different foods and get a million different results, but right here, eliminating all other factors purely on time.

511
00:31:32,000 --> 00:31:36,000
A two-second exposure is supposed to a six-second exposure. There's no difference.

512
00:31:36,000 --> 00:31:39,000
They're almost identical, or they are identical.

513
00:31:39,000 --> 00:31:41,000
Yeah, so that's an excellent result.

514
00:31:41,000 --> 00:31:46,000
The final bell has told, and this myth looks out for the count.

515
00:31:46,000 --> 00:31:48,000
Five-second rule. What's the verdict?

516
00:31:48,000 --> 00:31:53,000
Well, I think we were both pretty clear on what the results would be, and it took a little while, but we got it.

517
00:31:53,000 --> 00:32:00,000
There's absolutely no correlation between how much bacteria food picks up and how much time it has spent on the floor.

518
00:32:00,000 --> 00:32:04,000
In fact, it seemed like it was all about everything else but the time.

519
00:32:04,000 --> 00:32:15,000
It was how moist the food was, the surface geometry of the food, what was on the floor and how contaminated it was, and all those kinds of things, but it wasn't about the time.

520
00:32:15,000 --> 00:32:19,000
I had to figure out a bunch of other cool stuff, like the toilet seats, the cleanest place in your shop.

521
00:32:19,000 --> 00:32:25,000
And your mouse dirtier than a dog's. And speaking of which, are you going to let your kids eat off the floor?

522
00:32:25,000 --> 00:32:32,000
Well, I'm raising them off of your life story that you told me. I figure if they eat off the floor until they're eight or ten, they'll have a super-hardy constitution.

523
00:32:32,000 --> 00:32:35,000
Yeah, right. Well, the myth is busted one way or another.

524
00:32:35,000 --> 00:32:36,000
It's totally busted.

525
00:32:36,000 --> 00:32:38,000
Bada-bing, bada-boom.

526
00:32:45,000 --> 00:32:47,000
There you go. Beauty.

527
00:32:47,000 --> 00:32:51,000
Or is the ancient early warning system a mute myth?

528
00:32:58,000 --> 00:33:02,000
Morning has broken at the walled city of ancient China.

529
00:33:02,000 --> 00:33:04,000
What? Look out for the tree!

530
00:33:04,000 --> 00:33:08,000
The day is dry and clear, but what about the alarm hole?

531
00:33:09,000 --> 00:33:14,000
The build team is praying that it hasn't turned into a pond overnight.

532
00:33:17,000 --> 00:33:19,000
Moment of truth. I'm nervous.

533
00:33:22,000 --> 00:33:24,000
Not bad. Not bad at all.

534
00:33:24,000 --> 00:33:27,000
I see. I mean, there is some mud on this side.

535
00:33:27,000 --> 00:33:28,000
So...

536
00:33:29,000 --> 00:33:30,000
That side's gross.

537
00:33:30,000 --> 00:33:31,000
Yeah. You know what?

538
00:33:31,000 --> 00:33:33,000
This is good. I think this is going to be perfect.

539
00:33:34,000 --> 00:33:35,000
Phew!

540
00:33:36,000 --> 00:33:38,000
I didn't sleep so good last night.

541
00:33:40,000 --> 00:33:47,000
Before they lower the drum, Grant wants to test the geophone to make sure that it can detect the tunneling army.

542
00:33:49,000 --> 00:33:51,000
Okay, and contact.

543
00:33:54,000 --> 00:33:55,000
And ready.

544
00:33:55,000 --> 00:34:00,000
I got something very faint. I think I might be able to pick it out.

545
00:34:00,000 --> 00:34:02,000
Carrie, did you hear anything?

546
00:34:02,000 --> 00:34:04,000
I can't hear anything with my naked ear.

547
00:34:04,000 --> 00:34:07,000
The experiment set up is spot on.

548
00:34:07,000 --> 00:34:14,000
Jamie's digging is out of ear shot, but the geophone can detect faint tremors through the earth.

549
00:34:14,000 --> 00:34:20,000
Now they'll see if the drum can pick up the vibrations with enough resonance to be heard.

550
00:34:20,000 --> 00:34:23,000
The ancient amplifier is lowered slowly into its earthy socket.

551
00:34:23,000 --> 00:34:24,000
Okay.

552
00:34:25,000 --> 00:34:26,000
There we go.

553
00:34:26,000 --> 00:34:27,000
Let's aim it.

554
00:34:28,000 --> 00:34:29,000
There you go.

555
00:34:29,000 --> 00:34:30,000
Beauty.

556
00:34:32,000 --> 00:34:38,000
So for the first time in more than half a century, this mine will ring to the sound of a swinging pick.

557
00:34:39,000 --> 00:34:42,000
But will the talking drum warn at the end of the day?

558
00:34:42,000 --> 00:34:43,000
I'm not sure.

559
00:34:43,000 --> 00:34:44,000
I'm not sure.

560
00:34:44,000 --> 00:34:45,000
I'm not sure.

561
00:34:45,000 --> 00:34:46,000
I'm not sure.

562
00:34:46,000 --> 00:34:47,000
I'm not sure.

563
00:34:47,000 --> 00:34:48,000
I'm not sure.

564
00:34:48,000 --> 00:34:53,000
But will the talking drum warn Adam and Carrie that invaders are on their way?

565
00:34:53,000 --> 00:34:57,000
So Jamie, if we find gold, are you going to share it with me?

566
00:34:57,000 --> 00:35:02,000
50 feet away, Jamie and Tori are going to play the part of the tunneling Chinese army.

567
00:35:02,000 --> 00:35:06,000
Strike, two, three, and one.

568
00:35:06,000 --> 00:35:11,000
They swing quickly into rhythm, aiming hefty blows at the hard rock.

569
00:35:11,000 --> 00:35:15,000
Four, five, six.

570
00:35:15,000 --> 00:35:20,000
The mine shaft is might so Grant can clearly hear the pick's percussion.

571
00:35:20,000 --> 00:35:25,000
He'll keep an eye on Adam and Carrie, who will signal if they hear a drum beat.

572
00:35:25,000 --> 00:35:32,000
According to the myth, citizens with extraordinary hearing were selected to man these listening posts.

573
00:35:32,000 --> 00:35:36,000
Begging the question, why deaf is a post-Adam is on the job?

574
00:35:37,000 --> 00:35:38,000
Ten.

575
00:35:39,000 --> 00:35:40,000
Eleven.

576
00:35:40,000 --> 00:35:45,000
The drum's in an auditory black hole, but Carrie seems to be picking up something.

577
00:35:46,000 --> 00:35:47,000
Eighteen.

578
00:35:48,000 --> 00:35:49,000
Nineteen.

579
00:35:50,000 --> 00:35:51,000
Twenty.

580
00:35:51,000 --> 00:35:52,000
That's twenty.

581
00:35:53,000 --> 00:35:54,000
Stand by for playback.

582
00:35:54,000 --> 00:35:58,000
The geophone did record the sound, but only just.

583
00:36:00,000 --> 00:36:01,000
So faint.

584
00:36:01,000 --> 00:36:03,000
So how about the drum?

585
00:36:04,000 --> 00:36:08,000
It sounded like a really low hum, and then every time you hit it, it would go,

586
00:36:08,000 --> 00:36:12,000
as if somebody had just barely just going on the drum.

587
00:36:12,000 --> 00:36:14,000
I can't believe that it worked.

588
00:36:14,000 --> 00:36:16,000
It's just, that's incredible.

589
00:36:16,000 --> 00:36:17,000
I can't believe it either.

590
00:36:17,000 --> 00:36:19,000
I'm just, I'm amazed.

591
00:36:21,000 --> 00:36:22,000
It's quite a result.

592
00:36:22,000 --> 00:36:27,000
There seems no doubt that Carrie really was hearing the blows as they happened.

593
00:36:27,000 --> 00:36:30,000
I believe that the noise was definitely coming up the shaft.

594
00:36:30,000 --> 00:36:33,000
I believe the shaft was giving me a little bit of an echo.

595
00:36:33,000 --> 00:36:37,000
There was a lot of ambient noise around above me, birds and shuffling,

596
00:36:37,000 --> 00:36:39,000
but it was very, very different.

597
00:36:39,000 --> 00:36:40,000
I didn't hear it from this year.

598
00:36:40,000 --> 00:36:42,000
I only heard it from this year.

599
00:36:42,000 --> 00:36:45,000
So I firmly believe that the sound was coming from the drum,

600
00:36:45,000 --> 00:36:50,000
and it wasn't as much of a tap as it was a little beat.

601
00:36:51,000 --> 00:36:53,000
We brought out all of this fancy instrumentation.

602
00:36:53,000 --> 00:36:55,000
I mean, look at Grant.

603
00:36:55,000 --> 00:36:58,000
He's completely wired up, earphones, geophones, all that, microphones.

604
00:36:59,000 --> 00:37:01,000
The Chinese invasion alarm seemed to work better.

605
00:37:01,000 --> 00:37:03,000
This is the most exciting part about this job,

606
00:37:03,000 --> 00:37:07,000
is when you walk in with all of these preconceived notions of failure,

607
00:37:07,000 --> 00:37:08,000
like, ah, it's not going to work.

608
00:37:08,000 --> 00:37:09,000
No, there's no way.

609
00:37:09,000 --> 00:37:12,000
I don't think one of us thought this was definitely going to work.

610
00:37:12,000 --> 00:37:13,000
And then it does.

611
00:37:14,000 --> 00:37:16,000
Okay, here is position number two.

612
00:37:17,000 --> 00:37:19,000
Alright, maybe I can finally hear it.

613
00:37:20,000 --> 00:37:21,000
We're in a new location.

614
00:37:21,000 --> 00:37:23,000
We're underneath the drum.

615
00:37:23,000 --> 00:37:25,000
Jamie's going to strike the wall 20 times.

616
00:37:25,000 --> 00:37:26,000
You ready, Jamie?

617
00:37:26,000 --> 00:37:27,000
Okay.

618
00:37:27,000 --> 00:37:28,000
Everybody ready?

619
00:37:28,000 --> 00:37:29,000
We are ready.

620
00:37:29,000 --> 00:37:30,000
We are ready.

621
00:37:30,000 --> 00:37:35,000
Adam's hoping that the hearing trumpet will help overcome his limitations in the listening department.

622
00:37:35,000 --> 00:37:36,000
Striking.

623
00:37:36,000 --> 00:37:41,000
But past experience on Mythbusters suggests it may not be big enough.

624
00:37:41,000 --> 00:37:42,000
Watch that.

625
00:37:42,000 --> 00:37:43,000
You see, sonny?

626
00:37:44,000 --> 00:37:46,000
I can't hear you.

627
00:37:47,000 --> 00:37:51,000
One, two, three.

628
00:37:51,000 --> 00:37:56,000
Grant listens into the tunnel mic and counts off each blow of the pickaxe.

629
00:38:00,000 --> 00:38:07,000
Ten, nine, ten,

630
00:38:12,000 --> 00:38:17,000
sixteen, seventeen, eighteen.

631
00:38:21,000 --> 00:38:22,000
Okay, that's 20.

632
00:38:23,000 --> 00:38:24,000
Did you hear anything?

633
00:38:24,000 --> 00:38:26,000
No, I don't think I did either.

634
00:38:27,000 --> 00:38:31,000
We won't know until we go up there whether it made any difference.

635
00:38:31,000 --> 00:38:35,000
I'm not hearing quite so much reverberation here.

636
00:38:36,000 --> 00:38:37,000
Did you guys hear anything?

637
00:38:37,000 --> 00:38:38,000
Not that time.

638
00:38:38,000 --> 00:38:46,000
No, there were a couple of times when there was something that might have been it, but really, I started looking at your hands when you were counting off the hits.

639
00:38:46,000 --> 00:38:48,000
And I wasn't hearing anything.

640
00:38:48,000 --> 00:38:50,000
Alright, I didn't get much on the geophone either.

641
00:38:50,000 --> 00:38:57,000
So the invasion alarm seems to have a blind spot or rather, deaf spot, directly below it.

642
00:38:57,000 --> 00:39:04,000
For test number three, Jamie and Tari move to a new location 50 feet deep and over 100 feet away.

643
00:39:05,000 --> 00:39:06,000
Okay, I can hear them.

644
00:39:06,000 --> 00:39:07,000
The mic's set.

645
00:39:07,000 --> 00:39:10,000
So this is position three, chapel dugout.

646
00:39:12,000 --> 00:39:13,000
Ready?

647
00:39:13,000 --> 00:39:14,000
We're ready.

648
00:39:15,000 --> 00:39:16,000
Ten, one.

649
00:39:16,000 --> 00:39:19,000
Busting this myth can be backbreaking work.

650
00:39:24,000 --> 00:39:31,000
Nine, ten, eleven, twelve,

651
00:39:37,000 --> 00:39:40,000
sixty, seventeen.

652
00:39:43,000 --> 00:39:45,000
Okay, that's 20.

653
00:39:46,000 --> 00:39:47,000
Nothing.

654
00:39:49,000 --> 00:39:54,000
I think at that rate, we'll be inside the city walls in two months.

655
00:39:55,000 --> 00:39:57,000
I was watching your finger.

656
00:39:58,000 --> 00:40:00,000
Yeah, nothing. I didn't hear anything on that one.

657
00:40:00,000 --> 00:40:02,000
I was watching her finger.

658
00:40:02,000 --> 00:40:03,000
I did.

659
00:40:03,000 --> 00:40:04,000
You did?

660
00:40:04,000 --> 00:40:05,000
She did.

661
00:40:05,000 --> 00:40:07,000
The only time I couldn't hear it was when your jacket chuffled a little bit.

662
00:40:07,000 --> 00:40:08,000
Really?

663
00:40:08,000 --> 00:40:09,000
Yeah.

664
00:40:09,000 --> 00:40:10,000
Wow.

665
00:40:10,000 --> 00:40:12,000
I had my thumb like this and every time I heard it, I would...

666
00:40:12,000 --> 00:40:13,000
Yeah.

667
00:40:13,000 --> 00:40:14,000
And you were nailing it?

668
00:40:14,000 --> 00:40:15,000
Oh yeah, she was nailing it.

669
00:40:15,000 --> 00:40:16,000
She was nailing it.

670
00:40:16,000 --> 00:40:17,000
I was watching her.

671
00:40:17,000 --> 00:40:18,000
Wow.

672
00:40:18,000 --> 00:40:19,000
That's far.

673
00:40:19,000 --> 00:40:20,000
That is far.

674
00:40:20,000 --> 00:40:24,000
That's farther than test number two by actually a not insignificant distance.

675
00:40:24,000 --> 00:40:26,000
I can't believe we heard it.

676
00:40:26,000 --> 00:40:27,000
I mean, that's amazing.

677
00:40:27,000 --> 00:40:32,000
No army's going to tunnel 100 feet down before they start coming towards the city wall.

678
00:40:32,000 --> 00:40:37,000
So I'm thinking this scenario is a lot more likely that they'd just be that far out,

679
00:40:37,000 --> 00:40:39,000
but that's really far to hear it.

680
00:40:39,000 --> 00:40:40,000
Nice experiment.

681
00:40:40,000 --> 00:40:41,000
Nice design.

682
00:40:41,000 --> 00:40:42,000
Good rig.

683
00:40:42,000 --> 00:40:43,000
I'm just blown away.

684
00:40:43,000 --> 00:40:48,500
It's been a long day at the coal phase and the besieging army resurfaces to learn its

685
00:40:48,500 --> 00:40:49,500
fate.

686
00:40:49,500 --> 00:40:52,000
Well, what'd you guys find?

687
00:40:52,000 --> 00:40:56,000
We totally, totally heard it.

688
00:40:56,000 --> 00:40:57,000
It worked.

689
00:40:57,000 --> 00:40:58,000
Absolutely.

690
00:40:58,000 --> 00:41:02,000
It worked from there and it worked from position one and it worked from position three.

691
00:41:02,000 --> 00:41:04,000
It did not work from position two.

692
00:41:04,000 --> 00:41:10,920
Second location was a softer strata on the number one and the number three.

693
00:41:10,920 --> 00:41:15,920
We had good hard quarts and we could get a good throw at it.

694
00:41:15,920 --> 00:41:16,920
Yeah.

695
00:41:16,920 --> 00:41:18,920
The other one, I was hitting the roof with soft stuff.

696
00:41:18,920 --> 00:41:21,920
When you were hitting the quarts on that first test, Carrie heard it crystal clear.

697
00:41:21,920 --> 00:41:22,920
That is cool.

698
00:41:22,920 --> 00:41:23,920
Isn't that amazing?

699
00:41:23,920 --> 00:41:24,920
Yeah.

700
00:41:24,920 --> 00:41:26,800
I thought this thing would pick up anything.

701
00:41:26,800 --> 00:41:33,580
I couldn't hear a good thing, but Carrie's up here with a cone and Grant is counting off

702
00:41:33,580 --> 00:41:37,920
the hits and Carrie's not looking at him and she's matching him perfectly.

703
00:41:37,920 --> 00:41:38,920
It was beautiful.

704
00:41:38,920 --> 00:41:41,920
A lot of it when a plan comes together.

705
00:41:41,920 --> 00:41:47,920
Now the crazy thing is, we couldn't necessarily detect it on all of the equipment when we

706
00:41:47,920 --> 00:41:48,920
first did it.

707
00:41:48,920 --> 00:41:52,920
That this was so the drone was sensitive than the equipment that we bought.

708
00:41:52,920 --> 00:41:59,920
I got a little bit on the G-A-Bone, but the really expensive audio frequency mic didn't

709
00:41:59,920 --> 00:42:00,920
get anything.

710
00:42:00,920 --> 00:42:04,420
In a strange way, it makes sense because it's such a large surface area.

711
00:42:04,420 --> 00:42:10,180
So a small instrument, however sophisticated, might not work quite as well as just a great

712
00:42:10,180 --> 00:42:12,920
big diaphragm that is there receiving the sound waves.

713
00:42:12,920 --> 00:42:15,420
Well, are you guys ready to fill in a hole?

714
00:42:15,420 --> 00:42:16,420
Oh, man.

715
00:42:16,420 --> 00:42:18,420
I've been waiting for that all day.

716
00:42:18,420 --> 00:42:20,420
This should take us about...

717
00:42:20,420 --> 00:42:22,420
Jamie and I are going to see you back at the shop.

718
00:42:22,420 --> 00:42:23,420
You guys have to tell me.

719
00:42:23,420 --> 00:42:24,420
Really?

720
00:42:24,420 --> 00:42:25,420
I'm surprised.

721
00:42:25,420 --> 00:42:26,420
Shocking.

722
00:42:26,420 --> 00:42:30,420
Ladies and gentlemen.

723
00:42:30,420 --> 00:42:45,420
I can't believe that worked.

724
00:42:45,420 --> 00:42:46,920
So what do we think?

725
00:42:46,920 --> 00:42:50,420
Is it busted, plausible, or confirmed?

726
00:42:50,420 --> 00:42:54,660
Well, we know that it was written about in an ancient Chinese text, but we couldn't find

727
00:42:54,660 --> 00:42:57,420
any evidence physically that it ever existed.

728
00:42:57,420 --> 00:43:03,660
Yeah, but it is a fairly complex and esoteric system to write about if it wasn't used at

729
00:43:03,660 --> 00:43:05,420
some point successfully.

730
00:43:05,420 --> 00:43:07,420
So what do we call this, plausible?

731
00:43:07,420 --> 00:43:10,420
I'd say that meets the definition of plausible.

732
00:43:10,420 --> 00:43:11,420
Absolutely plausible.

733
00:43:11,420 --> 00:43:12,420
We agree.

734
00:43:12,420 --> 00:43:13,420
Amazing.