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Narrator: Albany, New York, December 1779. Born to a family of Scottish immigrants,
Joseph Henry would grow to become one of the greatest scientific
minds in American history.
Along with his contributions to science, Henry is known for serving
as the first Secretary of the Smithsonian Institution.
Henry considered himself above all else
a pure scientist. He was interested in finding out the truths of
nature - the principles of things - and he personally didn't care
for the application of those principles except
in a sort of playful way, as they related to education -
teaching of his students. Henry began his professional career as a
teacher at the Albany Academy,
and one of his major concerns there was developing
apparatus, devices, teaching tools, to show the principles of physics
to his students. And he knew -
he had earlier had some acting experience - so he knew
that an impressive demonstration would be much more effective
in capturing the interest of his students than just
a lecture without any kind of experimental illustration.
Henry became interested in electromagnetism
during this period when was teaching at the Albany Academy, and
electromagnetism was a
hot topic at that time. So now when Henry looked at the situation he
realized he could make a stronger magnet by winding
the wire more closely. But he knew that if the turns
touched, they'd short out. So he introduced the innovation of
putting insulation on the wire -
a very simple idea, and other people had sort of thought of it, but Henry is the first
to really do it.
And that allowed him then - he made his insulated wire, he was able to wind his
wire around very tightly. Not only that, he could put extra layers on top,
and with those two combined factors he could make very strong electromagnets -
much stronger than
any that existed before his time.
This is a magnet that Henry built for Yale College
in 1831. The core of it weighs 82 and a half
pounds and the manget was able to sustain a load of 2,000 pounds - one ton.
Henry developed his electromagnet and
realized that one of its applications was that could be controlled
at a distance through a long wire. And he came to that realization based on its
actual design. So to demonstrate this
for his class at Princeton, he set up in his lecture hall
an electromagnet with a wire and an arrangement by which he could ring a bell
at a distance in the classroom, to demonstrate the principle.
But this was purely a theoretical conception.
He had no idea that this could become
commercially successful. Henry personally
very much enjoyed searching for scientific truth.
He got a thrill, really, out of discovering something
new, creating, demonstrating a new effect.
Narrator: Henry's work in electromagnetism played a role in many other innovations
such as Samuel Morse's telegraph and Alexander Graham Bell's telephone.
Welcome to the electricity collections. This is our storage
area here at the National Museum of American History.
And one of the things we're going to look at this afternoon
is Samuel FB Morse's
prototype telegraph receiver.
And this is it. This is from 1837.
An artist's canvas stretcher with a wooden clockwork mechanism -
and what Morse is borrowing from Joseph Henry is the electromagnet design.
This electromagnet is basically the kind of thing Henry was working on
at that time - a horseshoe magnet wound
with insulated wire. And the idea is you pass a current through the wire
and it intensifies the magnetic field -
makes the magnet much more powerful.
Narrator: At the core of many key inventions was Henry's electromagnet work.
Examples of such inventions are preserved at the Smithsonian's
National Museum of American History.
Near the end of his life when Henry was
still Secretary of the Smithsonian,
young Alexander Graham Bell came to him for help.
Bell had had the idea for the telephone, but he didn't know very much about
electricity. So he came to see Secretary Henry
for help. They had a meeting in Henry's office.
Bell demonstrated what he had, and Henry was quite excited about this.
But then Bell had a problem. He said to the Secretary,
"Mr Henry, I really don't know very much about electricity.
How can I get the - how can I learn more?"
And Henry just said,
"Go out and get it! Get the knowledge you need."
And Bell reported later to his parents that this
really made the difference. He was inspired then to learn about
electricity and was able then to make the telephone a practical invention.
Narrator: Henry was propelled by his passion for discovery, his love of pure science.
As Secretary of the Smithsonian, it was Henry's dream to democratize science,
to make knowledge accessible to the public.
So in Henry's day, just as in our day, there's always been a tension
between the supporters of pure science and supporters of applied science.
Science of any kind costs money, today as in Henry's day.
The difficulty is that the payoff for pure science
is not immediate. With applied science you
spend some money to figure something out, and within a few years you can get
something that can be used.
With pure science that
may not happen for decades - it may not ever happen.
The payoff for pure science is more intellectual and aesthetic.
The steam engine in Henry's day was an object of great interest,
and it's a good example of applied science.
Pure science shows the thermodynamics of how it works, that is
the behavior of steam and gases as they
change their volume, as they change their pressure with changing temperature.
The applied science refers to
how you can use those principles to actually make an engine run,
make, for example, a train run on its tracks.
Narrator: Henry looked at scientific research almost as poetry.
By the work of others pursuing his art, Henry scientific interests have paid
dividends not only in the field of communication,
but in the study of light as well.
My name is Steven Turner. I'm curator of physical sciences
at the National Museum of American History.
I've been at the Smithsonian for about 26 years now.
I originally was here working in the exhibits department and then later
switched over to work in curatorial affairs,
and now take care of the physical sciences collection
which includes Joseph Henry's prism.
For me the prism has a special meaning because the
it illustrates a phenomenon of light called
total internal reflection, in which all the light that
goes into the prism reflects back out. And that's why when you
turn the prism to a certain place,
it appears to be a three-dimensional object inside of it.
In particular, Henry was interested in light, because light was
the new frontier in physics at the time.
The wave theory of light had just finally become established in Europe,
and Henry was anxious to bring this new information
to the United States. As the first Secretary of the Smithsonian,
Joseph Henry saw himself
as having an important role in American science -
that he not only wanted to establish the Smithsonian as an institution,
but he wanted to promote scientific knowledge within America. He thought that
it would lead to progress in America and make America a better democracy.
Narrator: Given Henry's interests, what would he think of
today's cutting-edge imaging technologies?
Here at the Smithsonian Institution, a team of 3-D digitization coordinators
known as the "Laser Cowboys"
carry on Henry's dream of democratizing science
through their work in laser scanning and 3-D printing.
So, all laser scanners are a little bit different, but in this instance
a laser beam bounces off this 45-degree angled mirror,
off of an object, back into the sensor - the mirror actually rotates
and then the whole entire scanner will slowly rotate as well.
So you're actually capturing in a spherical direction, so you can scan entire rooms,
archaeological digs, exhibit halls, really large things with a scanner like this.
So essentially what we're doing when we document an object in 3-D is taking
millions and millions of measurements.
Just like in the past when somebody would take an individual point-to-point
measurement with a pair of calipers or a tape measure.
In order to take it to the next step, we use our computer software
to essentially connect all the dots. So we have millions of points,
we connect all the dots, and create a
virtual surface. And that virtual surface can reflect light,
we can then calculate volume. If we wanted to 3-D print the object,
we could do that at this point. So that's really the strength of 3-D scanning and
3-D objects, is once you've invested the time
and the resources into creating a 3-D digital surrogate
of a Smithsonian object or research site, you have many possible deliverables.
You can create a a 3-D print for scientific inquiry,
you could put that object up on the Web so people can spin it around
and take measurements.
So if you're not able to come to the Smithsonian, you could still get
access and experience an object virtually.
So one of the most exciting implications of 3-D laser scanning is the
ability to 3-D print replicas.
So here we have a 1:1 scale replica of Abraham Lincoln's life cast.
This is printed in a plaster-like material with very high resolution.
And perhaps more exciting than a 1:1 replica which can be
quite expensive to create,
is the ability to create smaller replicas in lower-cost materials.
So here we have a replica made in a 1:4 scale,
and this is made out of ABS plastic, so this is only a few dollars to print.
Additionally the 3-D printers are actually very low cost as well,
only a couple thousand dollars in general. So this means that enthusiasts
at home, or teachers in the classroom, can implement 3-D
printing technologies quite easily now.
So with 3-D printing you start out with a 3-D model. That 3-D model is sometimes
3-D scanned. So we take our scan, we input that into 3-D printing software,
and it essentially slices it into many, many 2-D layers. This isn't too far off
from a 2-D printer you have at home.
In this case this printer extrudes
a thin layer of plastic, one layer at a time,
hundreds or sometimes thousands of times. So each time it
extrudes a 2-D layer, the bed drops down
a fraction of an inch essentially, and prints another layer, and so on and so on until
you have your fully three-dimensional object.
So in the past few years we've seen the democratization of 3-D
printing happening in a really big way.
And so those two things combined, we think, are going be really powerful. So the
democratization of 3-D capture using simple input devices
like a cell phone, an iPad, a point-and-shoot camera,
combined with a low cost 3-D printer, that's
two really powerful technologies that are sort of just beginning to
come together in a big way.
So that has huge implications for museums and for the world, I think.
Narrator: Today, as in Henry's day,
knowledge gained through scientific research informs cutting-edge innovation
in ways that we can only begin to imagine.
It's interesting to think how Henry would have seen
what we're doing today, because the electromagnetism and light
all being related, his interest in it as a pure science,
but his faith that someday it would evolve
into a new technology - a new tool for people to use -
has borne fruit in the new imaging that we're seeing, the three-dimensional
imaging that were seeing done at the Smithsonian.
So I think he would feel both proud and
somewhat inspired that his work
bore such engaging fruit.
Narrator: As Joseph Henry once said, "The seeds of great discoveries are
constantly floating around us,
but they only take root in minds well-prepared to receive them."
For young scientists chasing their dreams today,
look no further than Henry's message to Alexander Graham Bell:
"If you don't have the knowledge you need, go get it!"