The Action Lab's James Orgill writes, "In this video I show you how it is possible to contain the fire from a burning ball of propane in a wire mesh." Yes, it is possible. But that doesn't mean you should do it. In fact, you shouldn't.
The experiment demonstrates the phenomenon behind the Davy Lamp, a lamp that Sir Humphry Davy invented in 1812 for use in coal mines. From Wikipedia:
The lamp consists of a wick lamp with the flame enclosed inside a mesh screen. The screen acts as a flame arrestor; air (and any firedamp present) can pass through the mesh freely enough to support combustion, but the holes are too fine to allow a flame to propagate through them and ignite any firedamp outside the mesh. It originally burned a heavy vegetable oil.
The lamp also provided a test for the presence of gases. If flammable gas mixtures were present, the flame of the Davy lamp burned higher with a blue tinge. Lamps were equipped with a metal gauge to measure the height of the flame. Miners could place the safety lamp close to the ground to detect gases, such as carbon dioxide, that are denser than air and so could collect in depressions in the mine; if the mine air was oxygen-poor (asphyxiant gas), the lamp flame would be extinguished (black damp or chokedamp). A methane-air flame is extinguished at about 17% oxygen content (which will still support life), so the lamp gave an early indication of an unhealthy atmosphere, allowing the miners to get out before they died of asphyxiation.
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A massive boom heard Wednesday night over Puget Sound on the northwestern coast of Washington was most likely an exploding meteor. Or that's what They want us to believe anyway. The American Meteor Society registered a dozen reports. Video above. Keep your eyes on the upper left of the frame.
"The more I read the more inclined I am to believe this was a fireball (which is a meteor that is larger and brighter than normal)," the American Meteor Society's Bob Lunsford said. "I'm certain now that this was a meteoric event."
From KOMONews:
Most meteors' explosions are heard about a minute or two after they explode due to the time it takes the sound to reach the Earth's surface, Lunsford said. Sound travels at 767 mph in standard atmosphere conditions, indicating this fireball exploded some 35 miles away.
"If this was larger than normal then the sound could have originated from a higher altitude. So a delay of 3 minutes is entirely possible," Lunsford said. "Meteors become visible at a height of around 50 miles so your estimate is well within that range."
Lunsford said because there was a boom, it’s very likely there are small, rock-sized pieces of the meteor somewhere on the ground. When a meteor causes a boom, it’s “pretty far down” in the atmosphere.
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Above, a visit to a building in Liuyang, China where stacks of roman candle tubes and pop-its cover the floor. This is a fireworks machine trade show, where companies purchase contraptions for cranking out explosions of all kinds. Liuyang is commonly known as the fireworks capital of China. Here are some of the captivating machines that make (or break) July 4th and New Years Eve in the US.
(Props to Tasick Media on YouTube)
And as a bonus, here's a video of another machine that was used for manufacturing M-80s before they were outlawed in the US in 1966 (unless you have a license):
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In Halifax, West Yorkshire, England, a gentleman's car exploded after he reportedly sprayed "excessive" amount of air freshener and then lit a cigarette. From the BBC News:
Gas from the spray ignited, blew out the windscreen and windows and buckled the doors but the man escaped with only minor injuries.
Police said the incident in Halifax on Saturday "could've been worse" and warned people to follow safety advice.
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Someone dropped donated a live mortar shell to Goodwill in Placerville, Califonia. While the shell, thought to be leftover from World War II, would likely have fetched more than the usual bric-à-brac on offer, the organization is clear that they don't accept donations of live ammunition. From CBS Sacramento:
Goodwill says people often drop off items in boxes that haven’t been looked through, and sometimes the donations are from a deceased war veteran...
“As we sort through those things we often find war memorabilia, grenades, it’s rare that we find a live grenade or any live ammunition, but when we do we have protocols in place to make sure that we dispose of it safely,” said Richard Abrusci, President and CEO of Goodwill Sacramento.
In the case of this potentially explosive mortar, the bomb squad came in to take it away and disposed of it at Travis Air Force Base.
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"Fireworks," a classic by PES. Happy Independence Day!
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near which the water pipe passed.
(KVN via DIGG)
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Mike Armstrong had just walked over a grate in downtown Toronto when this happened:
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