Protected By Science My hand is like a red-hot poker to the liquid nitrogen, but an insulating layer of nitrogen gas forms- a phenomenon known as the Leiden-frost effect- keeping my hand safe and warm for a fraction of a second. Mike Walker
When I first saw this photograph of a manís hand submerged in liquid nitrogen at somewhere below -320į F, my immediate thought was, ďThat guy must be crazy! One second in that stuff, and youíre shopping for new skin!Ē My shock was tempered only slightly by the fact that it was my hand, and weíd taken the picture just a minute earlier.
I hadnít realized that my hand was quite so deep into the liquid. Amazingly, I barely felt the cold at all. My skin didnít get hurt for the same reason that water droplets dance on a hot skillet. An insulating layer of steam forms almost instantly between the water and the metal, keeping the droplets relatively cool as they float for several seconds without actually touching the hot surface. To liquid nitrogen, flesh is like that skilletóa surface hundreds of degrees above its boiling point. So the moment my hand touched the liquid, it created a protective layer of evaporated nitrogen gas, just as the skillet created a layer of steam. That gave me just enough time to put my hand in and pull it out again. Any longer than that, and frostbite would have set in.
Hot Water: Droplets on a very hot skillet take longer to evaporate than they would on a less-hot surface where no insulating gas layer forms. Mike Walker
The phenomenon is called the Leidenfrost effect (after Johann Gottlob Leidenfrost, the doctor who first studied it in 1756). Iíd known about it for years, but when it came time to test it in real life, I have to admit that I used my left hand, the one Iíd miss less.
I drew the line at another classic example of the effect. According to the books, itís possible to stick a damp finger directly into molten lead without getting burned, if you do it fast enough. After some consideration, and remembering the times Iíve been burned by molten lead, I decided that it probably wouldnít make a very good picture anyway.
ACHTUNG! Do not try this. If liquid nitrogen soaks into your clothes, you will not be protected by the Leidenfrost effect, and you can get frostbite very quickly.
Anglo-Saxon Sword and Helmet from Staffordshire Hoard Reconstructed 2015-05-29 0:49
Thousands of metal fragments from the Staffordshire Hoard have been reconstructed into two "significant" new 7th Century objects.
Researchers have pieced together parts of a silver helmet and a previously unseen form of sword pommel.
The hoard, which is valued at ¬£3.2m, was found in a field near Burntwood, Staffordshire in July 2009.
Both items have been put on display at Birmingham's Museum ...
ALEC corruption: Legislators and corporate lobbyists meet in secret at Savannah resort 2015-05-28 23:59
The Georgia Legislature has a message for voters: don't ask us about our meetings with corporate lobbyists behind closed doors.
The 11Alive Investigators tracked lawmakers to a resort hotel in Savannah last week, where we observed state legislators and lobbyists mingling in the hotel bar the night before they gathered in private rooms to decide what new laws would best serve ...
Swedish politician: US is the true cause of the masses of refugees from the Middle East 2015-05-28 20:13
Editors Note: And who controls US foreign policy? Listen to Jeff Gates.
The present Swedish debate about war refugees from the Middle East is an example of peer restricted expression. In the name of political correctness or perceived decency, any questioning of maximum generosity in opening Swedish borders for the refugees is indignantly rejected by the official mainstream. We have a ...
Even if Patriot Act Expires, Government Will Keep Spying on All Americans 2015-05-28 19:52
Government Will Use "Secret Interpretations" to Get Around Legal Prohibitions
Mass surveillance under the Patriot Act is so awful that even its author says that the NSA has gone far beyond what the Act intended (and that the intelligence chiefs who said Americans aren't being spied on should be prosecuted for perjury).
Specifically, the government is using a "secret interpretation" of the ...
The TPP, Monsanto, Rockefeller, Trilateral Commission, Brzezinski 2015-05-28 19:18
All hands on deck for global, economic, corporate dictatorship
There are dots to connect here. They're real, and they're spectacular.
Let me begin with a brief exchange from a 1978 interview, conducted by reporter Jeremiah Novak. He was speaking with two American members of the Trilateral Commission (TC), a group founded in 1973 by David Rockefeller and his intellectual flunkey, Zbigniew Brzezinski.