« Special: Mega-Movie Myths | Main | Episode 62: Killer Cable Snaps, Pottery Record »

This site is not affiliated with the Discovery Channel or MythBusters. Please visit the Official MythBusters site for official content.

Episode 61: Deadly Straw, Primary Perception

  • A hurricane can blow a piece of straw through a palm tree: busted
  • A hurricane can blow all the feathers off a chicken: busted
  • Primary perception: All living things are interconnected by ESP and have emotions: busted

The primary perception myth was the kooky myth of the episode and it started off on a weird note: they actually got a polygraph to react to Tory's thoughts of harming a plant. As they improved their experimental setup, though, these weird results disappeared.

The hurricane-related myths saw the construction of a new MythBusters air cannon. This one couldn't fire chickens -- just at them -- but it did feature an 80-foot-long barrel. It was a little scary as a straw gun; it was absolutely frightening as a piano wire gun.

Deadly Straw (Straw Through a Palm Tree)

Myth: In a tropical storm, the wind can become so powerful that a piece of straw can slice through a palm tree trunk

The highest ever recorded wind speed was 318 mph (Oklahoma City, 1999, recorded by doppler radar). There have been tests done at 100 mph that showed that straw could go through 2x4's, several layers of plywood, and even penetrate cinder blocks.


Jamie and Adam built an air gun to simulate the strongest possible hurricane wind: 318 mph. They were limited to 150 psi in the shop, so they compensated with the long barrel.

The air gun:

  • Air compressor
  • 4' air tank (SCH 40 pipe)
  • pressure gauge
  • valve. Pilot-assisted diaphragm valve
  • 80' long barrel (1/2" diameter copper pipe)

A test shot with a cotton ball at 8 psi went 321 mph, which was within 1% of their target speed.

They got their palm tree from Dale Motiska, who believed the myth was true as palm tree trunks are like cables made up of vascular bundles. Originally they setup a 20' tall, 3000 lb Washingtonia Robusta palm tree, but after carting that into the shop and setting it up, they found out that it doesn't grow in tropical storm territory. They replaced it with a queen palm, which is a California palm that is the closest cousin to the coconut palm they could obtain.

Straight tree test

A bundle of straw was breech loaded into the barrel with a cotton ball behind it to keep the air pressure up. The bundle of straw managed to penetrate about 3/8" into the tree close to their target speed of 318 mph. They next tried thatched reed, which is more rigid than straw and could be mistaken for it. The reed only managed 2" more of penetration into the trunk. This pretty much busted the myth for any palm tree greater than 2" in diameter.

For fun, they loaded piano wire into the gun and shot it at the tree. It went straight through the trunk, through a board behind the tree, and into the concrete wall.

Bent tree test

They next tested whether or not a bending palm tree would be more vulnerable -- perhaps the bending would open up the fibers in the tree trunk and make it more porous. They also setup the barrel at point blank range to give the straw the best possible chance.

They got nearly identical results as the original test with straw and thatched reed: they bending didn't help.


Chicken Feather Mini-Myth

Myth: A hurricane can blow all the feathers off a chicken

Their 318 mph gun couldn't blow the feathers off the chicken.


Adam: "We're just going to unload the strong air current right at him, you see, then i figured you could, you know, take it home and eat him."
Jamie: "I only eat things I kill myself"

Primary Perception

Myth: All living things are interconnected and can communicate at an ESP level. This means that plants have feelings and can even scream in response to a stressful situation.

Tory: "Is this a myth?"

See also:

The build team was testing the theory of Primary perception, which was advanced in the 1960s by Cleve Baxter, world polygraph expert and founder of the FBI's polygraph unit.

Stoelting #22600 polygraph tests

The Stoelting #22600 (Stoelting Web site) was the polygraph instrument that Baxter used in advancing his Primary Perception theory. The #22600 is an "Emotional Stress Monitor" with a pneumograph (force and speed of chest movements), a cardiograph (heart), and a galvanograph (galvanic skin response).

Before getting to the Primary Perception tests, Grant and Tory took turns hooked up to the lie detector while answering questions. Grant gave Tory rather mild questions but caught him lying when asked, "Have you ever lied about your age?" Tory asked more amusing questions and caught Grant 'lying' with the question, "Have you ever built or wanted to build a female robot?"

Stoelting test #1

They setup the plant and the polygraph inside a shipping container to shield the equipment from radar frequency/electrical interference. With Grant sitting in front of the polygraph and Tory standing nearby next to the plant, Tory proceeded to do various types of 'harm' to the plant:

  • hitting the plant: the needle (kymograph) deflected
  • fire extinguisher: huge spike
  • thinking about burning the plant: needle jumped

In all, the plant responded 35% of the time to Tory's stimuli.

The most surprising result was that the needle responded to Tory's thoughts about harming the plant, but as the later experiments noted, these first tests didn't do a good job of isolating the variables. With Grant and Tory standing right next to the sensitive polygraph, there were many ways in which their excitement and jumping around could have caused the instrument to respond.

NOTE: There were also clips of Tory actually burning the plant, but no results.

Stoelting test #2

Grant and Tory were shocked by results. They were worried that they were causing the needle to jump as a result of being next to the polygraph. They re-ran the experiment with Grant and Tory outside the shipping container.

Angry attack Evil attack Happy attack

Inside the container: plant responded 35% of the time to Tory's stimuli Outside the container: plant responded 28% of the time to Tory's stimuli

EEG test

They switched to an EEG instead of the polygraph. The original Baxter experiments used an EEG, so they felt this was in keeping with the original myth. This time there was no response when they re-ran the experiment with Tory's harmful thoughts to plants.

Yogurt test

They setup vials of yogurt 10' apart. Yogurt is made up of bacteria, so they thought that harm to one vial of bacteria should be felt by the other. Kari dropped hot water into one of the vials of yogurt while the EEG measured the response from the other vial. There was no response on the EEG.

NOTE: The vial of yogurt was placed on a pad of foam to isolate it from vibrations

Oral Leukocyte Test

This test checked whether or not Tory's own cells reacted to harm done to Tory. White blood cells were collected from Tory's mouth placed into a test tube, with a gold wire in the test tube connected to the EEG. Kari repeatedly shocked Tory with a stun gun, but the only response was from Tory himself. The white blood cells registered no response on the EEG.

NOTE: They made sure that the stun gun was far enough away from the EEG to not cause electrical interference

Egg Drop Test

They decided to redo their first experiment, but this time they really wanted to make sure that their own actions weren't interfering with the result. Inside the shipping container, which provided electrical shielding, they setup the plant and the polygraph. They placed the plant on top of foam to isolate it from vibration. Outside the container, they setup their Grant's fancy egg drop rig over a pot of boiling water. The egg drop rig was setup to select an egg at random to drop in at a random time -- thus there would be no anticipation. The entire crew exited the building for 45 minutes while the experiment went on.

The results: no response whatsoever

Although they had interesting results with the first couple of experiments, they felt that it was probably interference from vibration, electromagnetics, or themselves that skewed the instruments. Once they were able to remove these variables from the setup, they weren't able to get the same results.



TrackBack URL for this entry:

Post a comment

(If you haven't left a comment here before, you may need to be approved by the site owner before your comment will appear. Until then, it won't appear on the entry. Thanks for waiting.)