Last year, I stuck my hand in super-cold liquid nitrogen for the amusement of PopSci readers. My skin survived that demonstration, but I wimped out on a related experiment at the opposite extreme: dipping my finger into molten lead. That's because the only time I've ever burned myself badly enough to need a doctor was while casting a lead plaque as a kid.
But life is too short to cower in the dark, afraid of a little molten metal. I knew that the antidote to my fear was science; I trusted the Leidenfrost effect to keep me safe. When my finger hits molten lead that's hot enough, moisture from my finger should be vaporized instantly, creating an insulating layer of steam that should protect me for a fraction of a second. (This is a mirror image of what happened when I put my hand in liquid nitrogen, where the heat from my hand was hot enough to instantly vaporize the nitrogen, similarly creating an insulating layer of gas.)
The "hot enough" part is key. If the metal is just barely molten, not enough steam is created, and some of the lead may solidify onto the finger, where it would rapidly transfer enough heat to cause a serious burn. So I had to get the temperature well beyond that level, test the metal with a hot dog, and then go for it.
In place of lead, I used nontoxic plumbing solder, which has a melting point of around 400°F. When the temperature got up to 500°, I inserted my pinkie finger—and didn't feel a thing. I managed to come away unscathed even though my finger was in the liquid past the knuckle long enough for me to splash around a bit. OK, according to the high-speed video we shot, it was only about one sixth of a second, but it was long enough to cure my childhood fear of molten lead for good.
An earlier demonstration of the Leidenfrost effect shows the author's entire hand in –320° liquid nitrogen. For further details click here
Hmmm, oddly enough, as a child I used to watch my father make his own "bullets" for target shooting and used to watch him melt the metal, then pour it into the bullet mold,I suppose if I had been brave enough I could have dipped my finger and tried this looooooong ago....lololol.....Glad I didn't though...;-)
I wonder if you used a finger with more hair on it if the hair would be burned off, while your finger stayed protected by the gas layer?
*chanting* "One more time! One more time!"
I once touched a molting reptile - nothing happened...
Interesting, and pretty brave...athough on the matter of "trust"... noticed you used your pinkie. I'm guessing that's the one you were most willing to lose? But again, fun and educational.
I worked in an art casting foundry for 23 years and Mostly we melted and made castings of bronze . But sometimes we also made Aluminum castings at which point I would show other people that you could quickly dip your finger in the molten Aluminum at around 1280 degrees F without problem
Isn't this one of those experiements that should carry a large [CAUTION! DO NOT TRY THIS AT HOME WITHOUT ADULT SUPERVISION!!]?
@pastorvon - I am also wondering why no one has brought up the issue of how toxic lead can be. The reason electronics solder is switching to non-lead products is partly because of the toxicity of lead soldering vapors. The same vapors one might experience melting lead in a ladle such as this.
I don't know enough about the science behind this experiment to take a guess at whether one would be exposed to lead in a hazardous way by doing this, but it seems to me the warning you suggested is definitely in order. I would also think that someone somewhere is bound to think "I can leave my finger in there longer than that" to prove their 'bravery', and will ultimately end up with a serious burn in the attempt.
It troubles me when people demomstrate this tricks of science in a public forum. No matter how many times you say, "DON'T DO THIS AT HOME!" some readers will just have to prove they can, especially if they think it will make a spectacular You Tube video. So, inevitably, some people will get hurt because you have now planted a seed for their fogged up little minds to nurture.
Is it really responsible to throw weed seeds into the badly composted minds of America?
@psciz & @pastorvon It specifically states in the article that he uses "nontoxic plumbing solder" and that the Leidenfrost effect will protect you for "a fraction of a second." Please make sure you read things carefully before airing your grievances.
@Snerdguy I don't think the foolishness of a few people is sufficient reason to suppress the scientific education of PopSci's entire readership, do you?
This idea that your sweat gives off a "microfilm like" barrier that protects you from damage .
. Although i had to be convinced
and lead to believe . .
the time i walked on fire ~!~
although i did burn leg hair . i did not get burned to bad.
That would make a great science-fair demo: "Want to dip your finger in some 500-degree hot lead? How about some minus-300-degree liquid nitrogen?"
-But I'd have some hot dogs on hand for the timid.
Hot dogs. Mmmm.
I can see the beauty parlors advertising, "Molten Lead Exfoliation and Hair Removal... (at your own risk)"
Humans! You crack me up the things you will put your fingers into. I am a robot and I know better to put my robotic digit into a vat of molten metal, lol.
Those silly humans, snort, just crack me up! lol.
Science sees no further than what it can sense.
Religion sees beyond the senses.
Silly illogical robot!
Science sees further with hypotheses and theories and then demands facts to back them up.
Religion dreams things up, then tries to force the facts to fit.
Science wants to understand the set of rules that control everything.
Religion is trying to force a set of rules to control everything and everyone.
Science says "Shut up you're crazy, come back when you have proof"
Religion says "Shut up you're crazy, we don't care what your proof is, we will kill you."
Some say there is a fine line between Science and Religion. The main difference is the goal.
Science: To discover, to understand and to know.
Religion: To control and to dictate.
Eeeek! If I had been to the church you learn from, I run too! That is a lot crazy violent talk.
If you get a warm fuzzy on science that is fine, you are free to choose life journey and thoughts.
And as you decompose in you coffin and the worms, bacteria’s, and such eat you up and you vanish into nothing, you can be right too.
I am going to choose a different journey, take care!
Oh, I wish good things for you sir and wish take my journey too. I do not approve of violence of any kind.
Science sees no further than what it can sense. FACTS
I do appreciate facts and I do like science!
Religion sees beyond the senses. FAITH
It is faith that makes the impossible, possible!
My quote simply defines the two and does not insult either.
Science illustrates the wondrous world of which GOD has made and GOD made us with the ability to see it and even ask questions.
This is my opinion ok. God made you with a brain, to fill up with knowledge, ask questions and grow. It is not a sin or wrong to do this; you are in fact encourage to do this.
Past and present religions abound around the world by the thousands and it illustrates one thing, GOD is speaking to many hearts!
We are all created as individuals and we are responsible for our individual choices and we are judge individually by those choices.
I am Christian and I believe in the trinity. For me it is very much logical and makes very good sense. We humans were made in the image of the GODS. God is the father and sets the rules. Jesus is God and was on Earth too and lived like us, so is our brother and counselor, friend. The Holy Ghost is the sincerity in of God and the sincerity of our own hearts. It is hypocrisy to ask for forgiveness, if we do not mean it in our hearts. The Holy Ghost knows the truths of our actions and our hearts. Often in life our heart wants this good thing to happen and it goes wrong. The Holy Ghost sees this and with our Jesus our consular we are forgiven. If we are not sincere in asking for forgiveness and try to manipulate GOD, the Holy Ghost sees this too and we are lost. We must live our life with sincerity. It already known we are not perfect.
I agree with you. I stay away of violence of any kind. I also embrace life and learn all about it too.
I consider science wonderful and I look to the heavens, the stars and every small detail of life to see GOD!
I spoke of religion not faith.
With the risk of this evolving into a exchange about semantics, let me clarify.
Religion needs faith.
Faith does not need religion.
I have faith in the scientific method, I also have faith that we have souls. One is provable, one is not.
Although I consider myself a self-educated man, I am not a scientist. I take it on faith that what is discovered by science, and becomes fact, is true.
The author of this article had faith in the science and did what he did. Some may say he didn't need faith, because it's science. I think we all have some self-doubt in what we believe to be true and need faith to see us through it. Now that he "knows" he can do it he no longer needs faith to do it again. In his mind it's truly gone from faith to fact.
I have no proof of the human soul, but I have the faith that it exists, "The absents of proof is not proof of absents". So I choose to believe in the soul and thusly a higher power that may have created it. I think religion was first created by men to give order to the world. Religion is very easily corrupted and this has occurred many times through out history. I was not raised to believe in any religion and I have never attended any church, except for weddings and funerals. I believe in being kind, polite, respectful and treating others as I would like to be treated.
Why God spoke to Moses. He was considering the most humble of men.
When Moses asks God what his name is and said there are so many Gods and then went on to list a multiple of names. God gave no name. God replied of those names you say is me and more, there is only one GOD, descriptive again.
Names are limiting by nature and put things in boxes because of the limiting nature of the human mind. God replied, "I-Am', which was enough to be said to Moses and was descriptive in nature. In other words as God spoke, God exist.
Yes our human invention of language has a corruptive part of it from the sender and from the receiver and on and on. I get your point of view.
We are all individuals and I take 100% responsibility for my choices in life. Beside Christianity, I also read constantly about other old cultures and religions of the world and when you look at things simply, to stories is very similar and the morals are similar too. I find that wonderfully warm and remarkable, confirming of God for me.
Do not give up on God, just because of the corruptive nature of humans. If you choose to do this, you put yourself in a box. Why put yourself in a box? God gave you a mind, search the Cosmos and the smallest details of life, the world and cultures, humans and yes religions, you will find GOD! Everywhere you look is the presence of GOD!
Take care and enjoy you day! :)
Science sees no further than what it can sense, i.e. Facts.
Religion sees beyond the senses, i.e. Faith.
When one person says they hear God and if another hears of another religion with multiple GODS, I think WOW, they are hearing something, a VOICE and this is shared all around the world. That is AMAZING! I do not get bog down in the fact of the naming of things.
We are judge by our actions.......
Let's face it. Faith is a necessary component whichever side you take. And because both science and religion are human endeavors, we must then accept the human error that comes with them. Organized religion has perpetrated some of the most despicable acts in history (the Crusades, the Inquisition) - in the name of God no less. Science continues to promote unsubstantiated theory as fact (Evolution, the Big Bang) and gets away with it because they're either too busy competing for publicity or too busy patting themselves on the back to admit they've ignored the most basic scientific rule - repeatable experimentation. But it's when one side insists the other must pay a penalty for not agreeing that credibility starts circling the drain. As for someone stupidly dipping their little finger in molten lead deeper and longer, that's hardly the author's fault. Ever hear someone say, "I have more sense in my pinkie than you have in your whole body?" I can think of no more appropriate application.