Can a cracked valve on a compressed-air cylinder actually blast the tank right through a cinder-block wall? Could the Mythbusters get a speedboat to run on air cylinders, and could the build team get an engine running onballoonpowder?

Episode Viewers and Ratings

Season 4 Episode 21 of MythBusters resulted in a 0.00 rating in the 18-49 demographic.

MythBusters Season 4 Episodes...

• s04e01 - Paper Crossbow
• s04e02 - Shredded Plane
• s04e03 - Archimedes Death Ray Revisited
• s04e04 - Helium Football
• s04e05 - Franklin's Kite
• s04e06 - Cell Phones on Planes
• s04e07 - Bullets Fired Up
• s04e08 - Myths Reopened
• s04e09 - Mind Control
• s04e10 - Exploding Pants
• s04e11 - Crimes and Myth-demeanors 1
• s04e12 - Steam Cannon
• s04e13 - Killer Whirlpool
• s04e14 - Diet Coke and Mentos
• s04e15 - Shattering Subwoofer
• s04e16 - Crimes and Myth-demeanors 2
• s04e17 - Earthquake Machine
• s04e18 - Deadly Straw
• s04e19 - Mega Movie Myths
• s04e20 - Killer Cable Snaps
• s04e21 - Air Cylinder Rocket
• s04e22 - More Myths Revisted
• s04e23 - Exploding Lighter
• s04e24 - Concrete Glider
• s04e25 - Firearms Folklore
• s04e27 - Anti-Gravity Device
• s04e28 - Holiday Special
• s04e29 - 22,000 Foot Fall

MythBusters Show Summary

Did a Medieval Chinese astrologer make it into space by strapping rockets to his chair and setting them off? Just how hard IS it to find a needle in a haystack? Can you in fact go insane by having water drip on your forehead?

These are just a few of the myths, urban legends, and improbable sayings that the Mythbusters try to figure out. Comprised of special effects experts Adam Savage and Jamie Heineman - as well as their mottley crew of Mythbuilders, Mythterns, and resident 'crash test dummy' Buster - they don't just tell the myths, they put them to the test to see which ones are possible, and which ones are just plain bunk.