By the time you finish reading this article, you will undoubtedly think of Theo Gray when you hear someone say "mad scientist."
Theo, a columnist for the magazine Popular Science, recently published a book titled Theo Gray's Mad Science: Experiments You Can Do At Home - But Probably Shouldn't. The book is full of experiments so outrageous (Ignite your own phosphorus sun in a globe filled with pure oxygen! Make your own shotgun ammo by pouring molten lead off the roof! Heat a hot tub with 500 pounds of quicklime!) that it sounds like a parent's nightmare. It's actually quite the opposite: there's no a better way to spark the imagination of the young minds of proto-scientists than to bring science to life with Theo's hands-on experiments. Yes, these are dangerous experiments but that's why they're so much fun!Behind the gorgeous photos of each experiment, there is solid science explained in clear, accessible language with a little dash of humor that made Theo's monthly PopSci column so popular. You'll see. Let's dive into the excerpts of the Mad Science book. Here's Neatorama's premiere Spotlight article, 7 Mad Science Experiments You Can Do At Home But Probably Shouldn't, by Theo Gray ...
1. Gag with a Spoon: The Melting Spoon Prank
DISAPPEARING ACT - A steaming cup of water liquefies the spoon in
about 15 seconds - notice the puddle at the bottom of the cup. Photo:
With the right mix of metals, you can make an alloy that turns
to liquid at nearly any temperature.
Mention liquid metal, and people immediately think of mercury. After
all, it is the only metal that isn't solid at room temperature. Well,
not quite - it's the only pure metal, but there are many alloys (mixtures
of metals) that will melt well below that point. For example, the mercury-filled
fever thermometers that children were told not to play with in the 1950s
and '60s have been replaced by virtually identical ones containing the
far less toxic Galinstan, a patented liquid alloy of gallium, indium and
Those who were kids in that era may also remember playing with another
low-melting-point alloy: trick spoons that melted when you tried to stir
your coffee with them. These were made with a blend that, no surprise,
was highly toxic; it typically contained cadmium, lead, mercury or all
three. But, as it happens, it's possible to make alloys that liquefy in
a hot drink using safer components.
A few months ago I created a batch of these prank spoons as a gift for
my friend and fellow element buff Oliver Sacks (author of Awakenings
I cast jewelers' molding rubber around a fancy spoon to form the mold.
Then I looked up the formula for an alloy that would melt at 140 °F,
roughly the temperature of a cup of hot coffee, and found this one: 51
percent indium, 32.5 percent bismuth and 16.5 percent tin.
After the spoon turns to a puddle at the bottom of the cup, you can pour
off the liquid and touch the metal, feeling the weird sensation of it
hardening around your fingertip. When Sacks has used up all his spoons,
he can easily recover the metal, melt it again over a cup of hot water,
pour it into the mold, and make new ones - the trick-spoon circle of life.
So why can't you buy these nontoxic prank utensils in toy stores, as
you could the toxic versions of years past? Price. Indium costs about
three times as much as silver. (I get mine from a bulk supplier in China.)
Using gallium, you can make alloys that melt in lukewarm water or even
in your hand, but it's more expensive than indium, and it tends to stain
the glass and discolor skin. Unfortunately, no alloy replicates the low
cost, bright shine and nonstick fun of mercury. Too bad we know now that
playing with it for too long can give you brain damage.
How To Create a Melting Spoon
|WHAT YOU NEED|
Bismuth, indium and tin
Rubber or plastic spoon mold
Official webpage: Gag
with a Spoon
2. Calling Van Helsing: How to Build Your Own Werewolf Killers
BULLET PARTS - [from left] Bullion bars and rounds, the cheapest source
of pure silver; the graphite mold, opened after casting a bullet; the
profile bit used to machine the mold; silver bullets as cast and polished
to a mirror finish. Photo: Mike Walker.
(L) TURNING THE BIT - Using a lathe to create the milling bit that will
be used to make the graphite mold. (R) LIQUID METAL - Molten silver at
1,800 °F pours into a graphite bullet mold from an electric jewelers'
melting cup. Photos: Mike Walker.
Suss the myth from the reality with a hands-on investigation
into the original anti-werewolf weapon.
Like darning socks, making bullets is a dying art. Used to be just about
everyone with a need for ammo poured their own, using iron or even wooden
molds. These days only a few diehard hobbyists still do it, and they use
aluminum molds. But even fewer people still make silver bullets.
Actually, not many people ever made silver bullets. It's a difficult
process, and their efficacy against werewolves has never been scientifically
proven. I suppose their renown came from the perception that silver was
a distinguished metal, often spoken of in connection with its higher class
cousin, gold. But today silver is far more common, and it tarnishes over
time, primarily because of sulfur pollution from power plants. (By and
large, it didn't tarnish before the Industrial Age.)
I couldn't find any references describing real historical silver-bullet-crafting
techniques. At 1,764 °F, molten silver would ruin traditional and
modern bullet molds. They could have been fashioned using jewelers' methods,
but that would require a new plaster mold for every bullet. Frankly, I
think people spent a lot more time talking about silver bullets than they
did turning them out.
I don't like legends that are all talk, so I decided to see what it takes
to produce a real silver bullet: not plated, not sterling - pure silver.
To create the mold, I first had to construct a bit. I used a lathe to
turn a steel rod into a bullet-like shape, then used a milling machine
to cut away a quarter-circle wedge of the rod, leaving a sharp cutting
edge. Basically I had built a router bit shaped like a bullet. (I've fabricated
bits like this freehand with a file, which works fine; it just takes longer.
After using the bit to machine the graphite bullet mold, I used an electrically
heated graphite crucible to pour in the 0.999 fine liquid silver at about
2,000 °F, which is 230 °F above its melting point. The mold must
be preheated with a blowtorch to keep the silver from solidifying before
it fills the whole cavity. One of the benefits of using graphite is that
it keeps the silver from oxidizing, so bullets come out bright and shiny.
Would a silver bullet really fire? Probably. (Though, not being an experienced
gunsmith, I would never be foolish enough to try my bullets in a real
gun.) Bullets need to be fairly soft so that they can take on the shape
of spiral grooves in the gun's barrel, and pure silver is moderately soft.
It's also similar in density to lead, so it should have similar aerodynamics
and muzzle velocity. I'd guess silver would make a very nice nontoxic
substitute for lead in bullets. Too bad about the cost: These one-ounce,
large-caliber rifle bullets use about $12 worth of silver per shot - best
reserved for only the most severe werewolf infestations.
How To Build Your Own Werewolf Killers
|WHAT YOU NEED|
Several ounces of silver
Jewelers' melting cup
There are several ways to make mold suitable for casting silver.
This is the method I used, not necessarily the best method. Whatever you
do, don't ever try firing silver bullets out of real guns, which are designed
for lead ammunition. While relatively soft compared to other metals, silver
is still harder than lead and will act differently. The likely outcome
of such an attempt is death by explosive failure of the firearm.
Official webpage: Calling
3. Build Your Own Lightbulb
A VERY BIG BULB - The stick welder [left] provides enough juice to
heat a tungsten rod to nearly 5,000 °F. The ice bucket acts as the
bulb, and the helium displaces oxygen. Photo: Mike Walker.
Act as if you're smarter than Edison: Construct a lightbulb the
modern way with some helium and an old welder.
Thomas Edison famously spent months trying to make a lightbulb work.
He tested one material after another in an evacuated bell jar before he
finally got a carbon filament to burn long enough to sell it with a straight
face. When I had a free afternoon recently, I thought I'd see if I could
do it too.
Edison's first mistake was living before tungsten wire was available.
Tungsten is way better than carbon as a filament material, and now you
can find it in any metal-supply shop. It lasts longer, is less brittle,
and glows with a cleaner, whiter light. His second mistake, repeated in
classroom physics demonstrations to this day, was using a vacuum to get
the air out of the bulb. Clearing out the air is important because at
yellow to white heat (3,500 °F to 5,000 °F), pretty much all known
materials, even tungsten filament wire, react with oxygen and burn up
in a few seconds. Remove the oxygen, and the wire can't burn. But a vacuum
is the hard way to solve that problem. You need an expensive vacuum pump,
a thick glass bell jar to withstand the pressure of the surrounding atmosphere,
and several nonleaking pipe joints.
It's a whole lot easier to just displace the air with an inert gas that's
at the same pressure as the surrounding air, which is how most modern
bulbs work. Common household lightbulbs use a mixture of argon and nitrogen.
Fancy krypton flashlights and xenon headlamps use those eponymous heavier
noble gases to allow the filament to burn longer and hotter.
I used helium because it's easily available and lighter than air, allowing
me to fill my bulb, an upside down glass ice bucket (wedding present,
I believe), from the bottom. The helium floated up, displacing the air
inside. With a steady stream flowing in, I didn't even need to seal the
bucket very well - I just wrapped a sheet of tinfoil over the bottom to
keep eddies of air from wafting in.
For a filament, I used a thick tungsten wire I had lying around the shop
and, for the power supply, a small stick welder I got at an auction. It
supplied about 50 amps at 30 volts, giving me a 1,500 watt bulb. When
I powered up the filament without the bucket in place, it produced a prodigious
quantity of tungsten-oxide smoke and didn't last very long. But with the
bucket on and a steady flow of helium, the filament glowed brightly and
It must have been truly thrilling for Edison when he finally got one
of these things to work for the first time. I know I was thrilled, even
though I slaved over mine for only about 30 minutes and it worked perfectly
the first time - well, the first time I didn't forget to turn on the helium.
How To Turn a Jar Into a Lightbulb
|WHAT YOU NEED|
Tank of pure helium or argon
Tungsten welding rod or thick tungsten wire
Transparent bucket or large-mouth jar
Tinfoil or plastic wrap
Official webpage: Build
Your Own Lightbulb
4. Making a Deadly Sun
ONE BAD BALL - A white phosphorus 'sun'. The smoke is phosphorus pentoxide.
Photo: Mike Walker.
HUNK O' BURNING SUN - White phosphorus burning in air glows with a phosphorescent
beauty. Photo: Mike Walker.
(1) Suspend the white phosphorus in the center of a lobe filled with pure
oxygen. (2) The burning phosphorus rapidly fills the globe with thick
white smoke. (3) The chip of phosphorus burns energetically for more than
a minute. (4) CLOUDY SUN - It takes about a minute for the phosphorus
to burn itself up, leaving only smoke. Photo: Mike Walker.
From urine to firebombs - white phosphorus is among the nastiest
In 1669 the pompous German alchemist Hennig Brandt accidentally discovered
white phosphorus while boiling urine in Hamburg. He became the talk of
the town by demonstrating its amazing luminous powers to scientists and
In a cruel irony, 274 years later the discovery he'd hoped would turn
lead into gold instead turned his city to ashes when a thousand tons of
white-phosphorus incendiary bombs created one of the great firestorms
of World War II; 37,000 people died when the sky burned over Hamburg.
Yet even today, white phosphorus is still used as a weapon.
I've used red phosphorus to make a batch of kitchen matches. Although
both red and white phosphorus contain nothing but the pure element, red
is mostly harmless on its own, whereas white is near the top in every
category of dangerous. It'll ignite spontaneously and burn vigorously
until you deprive it of oxygen. One tenth of a gram inhaled is fatal,
and smaller doses over time can make your jaw fall off (seriously - it's
called phossy jaw).
The difference is that white phosphorus is a waxy paste consisting of
highly strained atoms bound into tetrahedrons. The energy in their chemical
bonds is bursting to get out, causing white's high reactivity. The atoms
of red phosphorus are linked in relatively stable chains. Same element,
very different properties.
Brandt was trying to turn lead into gold, and finding a substance that
glows in the dark seemed like a big step in the right direction. Of course,
it wasn't, and he died poor after spending two wives' fortunes on boiled
urine. (Alchemists were obsessed with urine because it's yellow and they
were trying to make gold. Transmuting lead into gold is possible, but
it turns out you need a nuclear reactor, not buckets of pee.)
Still, the discovery of white phosphorus was an important one in early
chemistry. These days it is used in many ways, including the phosphoric
acid in nearly all colas. It's also used in a particularly beautiful classroom
demonstration of its extreme flammability and brilliant yellow light.
Just hope you never see that light in your neighborhood.
How To Contain a Phosphorus Sun
|WHAT YOU NEED|
Half a gram of white phosphorus
Pure oxygen gas or liquid oxygen
about half a gram of white phosphorus in the center of a globe filled
with pure oxygen, then touch it with the end of a warm rod to ignite
burning phosphorus rapidly fills the globe with thick white smoke,
demonstrating one of its military applications: as a smoke screen.
chip of phosphorus burns energetically for more than a minute. The
resulting glowing ball is what gives rise to the term "phosphorus
DANGER ALERT: White phosphorus is extremely toxic: A tenth of
a gram can be fatal. It catches fire at a temperature only slightly above
room temperature and is illegal to possess in many states.
Official webpage: Making
a Deadly Sun
5. Trap Lightning in a Block
Freeze a charge screaming through solid plastic - or printer
toner - to see how electricity moves.
There are many unusual things to see around Newton Falls, Ohio - the
Wal-Mart with hitching posts for Amish buggies, the Army base with helicopters
and tanks proudly arranged on hills - but I was here for the most unusual
thing of all: the local Dynamitron. I was here to make frozen lightning.
The Kent State Neo Beam facility's Dynamitron is a four-story-tall, five-million-volt
particle accelerator much like a tube TV, only bigger (Yes, tube TVs are
domestic particle accelerators.) Both Dynamitrons and TVs use high voltages
and magnets to slam electrons into a target. In a TV, that's the phosphor
screen; in this Dynamitron, it's usually plastic plumbing components being
hardened by the beam. But when I joined the team of retired electrical
engineer Bert Hickman and physicists Bill Hathaway and Kim Goins, the
product was Lichtenberg figures, lightning bolts permanently recorded
in a block of clear acrylic.
With the Dynamitron - rented for the day - adjusted to around three million
volts, it blasts electrons about halfway through half-inch-thick pieces
of acrylic sheet. The plastic is a very good insulator, so it traps the
electrons inside. Coming out of the machine, the blocks don't look any
different, but they hold a hornet's nest of electrons desperate to get
Left alone, the electrons will stay trapped for hours, but a knock with
a sharp point opens a path for them to make a quick escape. Electrons
gather from all parts of the block, joining up to form larger and larger
streams of electric current on their way toward the exit point. As the
charge leaves, it heats up and damages the plastic along the branching
trails it follows, leaving a permanent trace of its path. If you could
see inside a thundercloud in the nanoseconds before a bolt of lightning
emerged, you would see the same kind of pattern. The bolt doesn't just
pop up fully formed; it has to gather charge from all over the cloud.
You can create similar, if less permanent Lichtenberg figures using toner
powder from a copier or printer and any common source of static electricity.
This is how German scientist Georg Christoph Lichtenberg first did it
in the late 18th century (he used powdered sulfur), which at the time
represented one of the great discoveries in the history of electricity.
Today, the figures are a great way to learn about electrical discharge
- and can make a cool souvenir from an afternoon with a very expensive
How To Make Your Own Lightning Pattern
|WHAT YOU NEED|
Wimshurst or Van de Graaff static electricity machine
Metal point and wire
Clean, dry, untreated acrylic sheet
a sharp metal point so it touches the center of a sheet of insulating
material. (Lichtenberg used resin made from tree sap; today, clear
acrylic works well.)
a Wimshurst machine, a Van de Graaff generator, or vigorous shuffling
on shag carpeting to build up static electricity, and then touch
the metal point with your finger or with the machine's electrode
to discharge it.
This forms a pattern of stranded charge on the plastic. The Lichtenberg
figure is there; you just can't see it.
toner powder over the surface. It will stick to the static electricity,
revealing a beautiful Lichtenberg figure. Lichtenberg's discovery
ultimately led to photocopiers and laser printers, where the charge
is laid down in patterns of words and images.
Official webpage: Trap
Lightning in a Block
6. Nickel Growing in Trees
WASTE NUT - These nodules of chrome and nickel build up over time
from the process of electroplating bumpers. Photo: Chuck Shotwell.
Electroplating uses electricity to turn dissolved ions into a thin layer
of solid metal bonded to a surface. Photo: Chuck Shotwell.
Electroplating makes bumpers shiny and rustproof. It also makes
these beautiful bits of industrial waste.
If there were a contest for most attractive industrial waste, these nickel-chromium
nodules would win hands-down. As intricate as the veins on a leaf, brighter
than a '57 Chevy in the noonday sun, they grow naturally in tanks of chemicals
simmering gently in a bumper factory somewhere in the Midwest. Eventually
workers whack them off with hammers and dump them in barrels for recycling.
Bumpers are stamped out of steel and elecroplated with a thousandth of
an inch of nickel (for rustproofing) followed by 65 billionths of an inch
of mirror-bright chromium (for shine). Everything you see is chromium,
yet it represents no more than a millionth the weight of the bumper.
Electroplating uses electricity to turn dissolved ions into solid metal
bonded to a surface. Bumpers sit in a vat of acid containing dissolved,
positively charged nickel ions. A current is run through the solution,
forcing negatively charged electrons from the bumper into each nickel
ion, neutralizing it. The ions bond to the bumper, plating it with a very
thin layer of solid metal. After the nickel is applied, robot cranes transfer
the bumpers to tanks of chromic acid, where the same process adds a coating
Titanium bolts and T-shaped wing nuts attach the bumpers to titanium
frames carrying about 10,000 amps at around three volts. The bolts, nuts
and frames are coated with rubber-like insulation, but it's never perfect.
Tiny cracks and nicks form over time, allowing electrons to escape and
the metal to start depositing. Bumpers go through the line only once,
but the frames and T-nuts are dipped repeatedly. Over dozens of chrome
and nickel baths, these wonderful nodules build up.
In a week, the factory I visited turns tons of nickel and chrome into
thousands of gleaming beauties. It also makes about 10,000 bumpers.
Official webpage: Nickel
Growing in Trees
7. Shattering the Strongest Glass
SHATTERED GLASS - A piece of tempered glass shatters all over from
a blow to one corner.
Explosive glass drops demonstrate why your car windshield is
so strong and safe.
If you want a scientific display of the dangers of pent-up stress, Prince
Rupert's drops are it. After the trauma of being dropped molten-hot into
a bucket of cold water, these glass balls, named for a 17th-century amateur
scientist, turn into bundles of high tension. They're impervious to even
the strongest blows, until you find their hot button: Flick the tail,
and they explode.
When molten glass hits cold water, its outer surface cools rapidly and
shrinks as it solidifies. Since the center is still fluid, it can flow
to adjust to the outer shell's smaller size. As the center eventually
cools and solidifies, it also shrinks, but now the outer shell is already
solid and can't change its shape to accommodate the smaller core.
The result is a great deal of internal stress, as the center pulls the
outside in from all sides. Like a tightly wound spring, the glass is set
to release a lot of energy. If you break the thin glass at the tail, a
chain reaction travels like a shock wave through the drop. As each section
breaks, it releases enough energy to break the next section, and so on,
shattering the whole drop in less than a millisecond.
Paradoxically, the same tension also makes the Prince Rupert's drop stronger.
Glass breaks when tiny scratches pull apart and spread into fractures.
Since the surface is compressed by internal stress, scratches can't grow,
and the glass is very difficult to break. I took a hammer to the thick
end of some drops, which I got from a local glassmaker, and they stayed
intact. Even the tail is stronger than it looks.
Tempered glass, common in cars and glass doors, works the same way. Jets
of cold air are used to rapidly (but not too rapidly) cool the surface
of hot sheets of glass, creating a milder internal tension that keeps
the surface compressed at all times. That's why tempered glass is extremely
strong but shatters into thousands of pieces when it does finally break.
This shattering actually makes it safer, because there are no large pieces
to act like knives or spears. The lesson here is that stress makes you
stronger but inside that tough exterior lurks a potential explosion. And
stay off my tail, OK?
How To Make and Break Glass
|WHAT YOU NEED|
Glass makers' furnace
Metal rod to pick up molten glass
Water about one foot deep
Note: Creating Prince Rupert's drop requires a glass-melting furnace,
typically a gas-powered kiln-type affair with a clay pot full of molten
glass. If you don't have one, find a local art glass studio and sweet-talk
your way in.
Official webpage: Shattering
the Strongest Glass
Theo Gray is the author of Popular Science magazine's "Gray
Matter" column, the proprietor of periodictable.com, and
the creator of the iconic photographic periodic-table poster seen in universities,
schools, museums and TV shows from MythBusters to Hannah
Montana. In his other life, he is co-founder of the major software
company Wolfram Research, creators of the world's leading technical software
system, Mathematica®. He lives in Champaign-Urbana, Illinois.
This article excerpts Theo Gray's Mad Science book with permission.
All images and text are copyright © by Theodore Gray.
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