Hi.
Good morning everybody.
How are you today?
This week, I want to talk to you about the bow and arrow, and something called the archer's
paradox, which I think is rather interesting.
Before that, as always, don't forget, if you click on the link in the About section below
here, you can find the script for this talk, you can find questions and you can find answers.
And, if you have any ideas for topics you'd like me to talk about, please put them in
the comments below.
And as always, if you like these talks, please subscribe and you can get them every week.
OK.
So, a bow and arrow.
Where ... when were the bow and arrow invented?
Well, we don't actually know, to be honest.
They probably existed about 64,000 years ago, probably.
Why don't we know?
Well, because, what is a bow and what is an arrow made of?
They are mostly made of wood, and the string is made of animal parts, dried animal sinew,
and the arrow is made of wood as well.
And what happens to wood?
Well, it disintegrates.
If you put it on the ground it biodegrades.
It gets eaten by bacteria and it disappears.
The same with trees outside that die.
However, the arrowhead, the top of the arrow, those sometimes last, and they last because
they're basically made of stone, or flint, or obsidian, which is a type of volcanic rock,
I think.
And, if you get shot with an arrow, the shaft of the arrow very well may biodegrade, but
the stone will not.
Now, generally, those stones look like regular stones, but quite often, if they're found
inside somebody, you can say, "Ah.
That was an arrowhead."
And, of course, arrows and spears are different because a spear head is much bigger than an
arrowhead, because it has to be weighted for the spear to fly correctly, which means an
arrowhead is much smaller.
So, if somebody ... if you find a skeleton with obsidian blades inside them, most likely
they were shot by an arrow.
So, we can guess that arrows and ... bows and arrows existed about 64 ... 65,000 years
ago, which was the Upper Paleolithic period of human life.
Now, these people were basically hunter gatherers.
The bow and arrow, they were used for fighting, but more than that,
they were used for killing animals.
Spears are good.
Spears can be thrown pretty far, but you've got to be quite strong to throw a spear and
it takes a lot of practice to be accurate.
A bow and arrow, you can fire a lot more arrows quickly and you don't have to be that talented
... that skilled to hit your target.
If you can fire ten arrows, one of them may actually hit your target.
So, as I said, bows and arrows generally don't survive.
So, from thousands of years ago, these don't exist.
Unlike swords.
I mean, swords are made of metal.
If you drop a sword, it's probably going to survive a few thousand years.
If you drop a bow and arrow, it will have disappeared within a few years.
So, we don't have any bows and arrows really.
Also, we don't have any record of them because people back then didn't have a written tradition.
So, it's very difficult to say when they actually came into existence.
We do know that they started in central Africa.
We have found flint and obsidian blades in Central Africa from thousands of years ago,
so we ... well, from actually ... er ... about fifty thousand years ago.
So, we know that that's where they started.
And they spread around the world from there.
Interestingly enough, they didn't actually get as far as Australia.
Australia ... the aborigines in Australia, they don't have a tradition of bow and arrow.
They use boomerangs instead.
Boomerangs actually have an advantage over a bow and arrow in that they can be lethal
at a greater distance.
If you're highly trained with a boomerang and you throw it, you can kill a kangaroo
2 ... 300m away from you, where a bow and arrow probably couldn't reach that far.
And, if it could reach that far, you'd very ... you'd be very unlikely to actually hit
your target.
So, a boomerang can be lethal at a greater distance.
Of course, a boomerang does take more training than a bow and arrow does, but that's probably
why bows and arrows never developed in Australia.
Also, Australia being an isolated island is probably another reason for that.
Anyway, we do have a bow and an arrow from about 9,000 B.C., about 11,000 years ago.
That was found in Denmark.
It's called the Holmegaard Bow, and it was found in a bog.
When it fell into the bog, it was protected from the bacteria ... protected from the things
that biodegrade wood ... and it was preserved as it is.
So, the oldest bow we have in existence is from 11,000 years ago in Denmark.
OK.
Now, the type of bow we found in Denmark was a straight bow.
Basically, a straight bow is about the length of a person.
It's made from one piece of wood.
Either elm, or maple, or cedar, or bamboo in Asia.
And that piece of wood was flexible, obviously, and it was strung with a piece ... with a
... with a bow string.
And this was usually made of animal sinew, dried animal intestines, or dried animal muscle
that was stretched.
And when you pull it, the piece of wood is flexible, it bends, it transfers energy to
the arrow.
And when you release it, it fires the arrow.
Now, bows like this, they have to be pretty big, basically, about the height of me.
Longbows like that could fire an arrow very very far, but you had to be extremely strong
to do it.
Now, these types of bows and arrows were the most common to begin with.
However, a bow that is as big as me is very difficult to use.
It's very unwieldy.
It's quite large.
So, when people started to ride horses, when you had the invention of the cavalry, you
couldn't ride a horse and use a longbow ... a full-sized bow.
So, the people in Asia, the Mongols basically, the nomadic peoples in Asia, they came up
with a different type of bow.
About 2500 B.C., they came up with a bow that is called a composite bow.
Now, what that is ... the basic straight bow is one piece of wood.
It's one single piece of wood.
A composite bow is made up of different pieces.
You have a piece of wood in the middle, then you have a piece of horn on the inside, and
then you have multiple layers of glued animal hide on the outside like this.
Now, a bow like that can be much much shorter because the horn, when you pull the drawstring,
the horn compresses and it stores energy.
And the hide on the other side expands.
And, because it is elastic, it will contract back to the original position.
So, a bow like that can transfer the same amount of energy to an arrow as a longbow.
And also be much much shorter.
You can use a composite bow while you're riding a horse.
However, composite bows are very very difficult to make.
They take a long time to make.
You have to season the wood, then you have to layer the wood with glues, and then you
have to layer the horn and glue that on, and then you have to layer the pieces of hide
and glue each one on separately as well.
It takes a long time to make.
And also, bows ... composite bows are very very susceptible to humidity.
If you live in a humid environment your bow is very likely to either warp or the glue
can actually come unstuck.
So, composite bows tended to exist in drier climates because they're not very strong in
humid climates.
And the Mongols were obviously famous for using the composite bows.
Genghis Khan, with his cavalry on horses, they were famous for being able to fire arrows
extremely quickly and extremely accurately.
And they of course used compound bows.
So that's the bow.
An arrow.
Arrows were generally made of wood again.
Ash, elm, willow, oak, bamboo, if you live in Asia of course.
That wood had to be flexible.
We'll talk about that in a second.
What do you call the basic parts of an arrow?
Well, up here at the end, where it nocks on to the drawstring, you have what's called
the nock.
Then the feathers.
My arrow doesn't have any feathers, of course.
Those are called the fletching.
The main part of the arrow is called the shaft.
And at the head, at the end, you have the head, the arrowhead.
A lot of names in England and America came from professions like this.
There is the name Fletcher.
A fletcher was the person who put the feathers on to the arrows.
There is a name Archer.
An archer was somebody that fired the arrow, of course.
A lot of professions from olden days have become names.
Like Goldsmith, or just Smith in general, I suppose.
Anyway, those are the parts of the arrow.
OK.
So, bows and arrows are extremely effective.
With a little bit of training, your average trooper, your average soldier, can fire it
quite a long way and can cause a lot of damage to an opposing army.
So, general battle would have archers in the distance who would fire arrows at each other,
and then the infantry, the basic people, would charge at each other, and they would fight
with swords and knives.
The archers of course, would stop firing once that happened because they didn't want to
hit their own troops.
However, of course, in the fourteenth century, guns started to be developed and once the
gun was invented the arrow stopped being so effective ... stopped being so popular of
course.
However, in the beginning, in the fourteenth century, when guns were invented, they were
too ineffective, they were too slow.
It took about a minute to load and fire a gun.
You had to put the charge down the barrel, then you had to put the ball down the barrel,
then you had to put the kindling on the top here, then you had to light it and spark it
and fire it.
It took about a minute all together.
Not very easy to fire of course.
However, in the eighteenth century, guns started to improve.
They became a little bit better and you could fire them a little bit faster.
Although, still not so fast.
Warfare starts to change around about then.
You have ... you have fewer of the two armies charging each other and more of two armies
shooting at each other.
basically.
Then, of course, the nineteenth century, guns were changed again.
You had the invention of the cartridge, the bullet and threaded barrels.
A threaded barrel means that when you fire the bullet it rotates, and it can go straight.
Before then, you basically had a ball, and the ball would spin everywhere, and you had
no idea where it was going to go.
Maybe, one out of ten bullets would actually hit the target.
But, once you have rifling ... a spiraled groove up the barrel ... you make the bullet
spin this way and it will go exactly where you want it to go.
Very very straight.
So, once that happened of course, the bow and the arrow disappeared.
Nobody has fought with these for hundreds of years.
Now, we just use them for sport and for hunting, of course.
All right.
I want to talk to you about something called the "Archer's Paradox" today.
A paradox, of course, is when two or more statements contradict each other.
For example, in time travel, we talked about the grandfather paradox.
You cannot go back in time and kill your own grandfather because that would negate your
being in the present and you couldn't make the time machine to go back and kill your
grandfather and it's a circle.
That's a paradox.
Well, the archer's paradox is this: If you have ... if you notch an arrow on your bow,
and you pull it ... generally the arrow goes this side of the bow ... where is my arrow
pointing?
It's pointing off to the left, over there.
My bow is pointing at the target.
If I point the arrow at the target, my bow is pointing off over there.
So, the archer's paradox is this: How can an arrow that's pointing away from the target,
hit the target?
That's the paradox.
Now, there are three ways that this paradox is solved.
Well, it's not really a paradox, I suppose, but there are three ways this works.
The first way is with a general longbow.
When you fire the arrow, because the arrow is made of a very flexible wood, the arrow
bends like this.
So, when I transfer the energy from the drawstring to the arrow, what actually happens is the
arrow bends like this.
The drawstring comes over here.
The arrow flexes this way, and bends like that, and then when it goes past the bow it
flexes back again, and it flexes through the air like this, as a snake, all the way down
until it hits the target.
So, because the arrow is flexible, the archer's paradox is not a paradox.
The arrow goes round the bow and hits the target.
People obviously knew that even though you were aiming at the target you could still
hit the target, but it wasn't actually proven ... people didn't know why that was until
the 1920s.
And what made it possible to prove was the existence of slow motion filming, of course.
Up until the 1920s, people couldn't video slow motion.
You can't see an arrow.
It goes too fast.
But, with slow motion video, you can actually see this movement.
And, if you look on YouTube, you can find lots of videos of an arrow doing this through
the air.
It's very very impressive.
So, the first way that the paradox was solved, well, the first natural way the paradox was
solved, was that: using a flexible arrow that curves itself around the bow.
The second way is done in Asia, in basic Japanese archery, kyudo.
What happens there is, the arrow is on the other side of the bow.
When you have an arrow on this side of the bow, as in most archery, the drawstring will
always hit your wrist here.
Like that.
So, you have to have a leather pad here on your wrist to protect your wrist.
In Japanese archery, the bow ... the arrow is on the far side of the bow, like this,
and you fire, like this.
And you pull the arrow back, past your head.
You pull your arrow back to about here.
So, generally, you have this kind of posture, with the arrow pulled back almost as far as
your ear.
And when you release it, again, you have the same problem.
The bow is pointing at the target, the arrow is pointing away from the target.
So, how can the arrow hit the target?
This is the archer's paradox again.
Now, the Japanese way of overcoming this problem is thus.
When you grip the bow in Japanese archery, you keep your hand very very tight, but not
on the bow itself.
You basically form a shape like this with your hand and your fingers press tight together,
but they leave a space in the middle there, and that space holds the bow.
So, when you pull the drawstring, the bow is resting against the space between your
thumb and your forefinger there.
You don't actually have to hold the bow.
Now, as you pull the bow, you start like this, as you draw the bow, it ro ... ... Ah!
I broke my bow!
This is my daughter's bow!
Oh dear.
She's not going to be happy!
... As you pull the bow ... as you pull the drawstring, the bow rotates in your hand,
and it catches against the loose skin and it becomes under tension.
And, when you fire the arrow ... when you release the arrow,
the bow rotates in your hand.
So, you fire the arrow this way, but the bow rotates, putting the arrow in line with the target.
You fire and the bow rotates in your hand and the arrow goes round, comes around in
line with the target, and does the same thing as a Western bow: it snakes through the air
like that, and hits the target.
So, that's the second way of overcoming the archer's paradox.
The third way of overcoming it.
Modern bows, of course, are not made of wood, they're made of many different materials.
And, because modern materials are much stronger than wood, are much stronger than composite
bows, you don't have to worry about the shape so much, so you can actually cut a space out
of the middle of the bow.
If you look at an Olympic archer, they pull their arrow ... they draw their arrow right
in the middle of the bow.
It goes through a space cut out of the bow, like this.
So, they are actually firing directly at the target.
So, the archer's paradox doesn't exist anymore with modern bows.
You can fire an arrow straight at a target.
I'm not very good at that.
OK.
That's basically the archer's paradox, and the history of the bow, which I thought was
quite interesting thank you for watching.
I thought I'd show you a little bit more about how to use a Japanese bow.
This is the arrow, of course.
Here's the nock, here's the fletching, the feathers, the shaft, and the arrowhead.
This is a Japanese bow.
This is a glove.
It's called a "kake".
This glove is made of deer hide and this is basically for catching the drawstring.
This is a hay bale over here.
You're not supposed to fire an arrow with feathers into a hay bale, but I'm going to
do it just so I can show you the arrow with feathers, itself.
As I was saying earlier, you don't hold the bow as tight as you do a Western bow.
And also, you fire the arrow on this side not on this side.
I'll try and show you.
I'm not very good, but I'll do my best.
OK.
So, we start like this.
We raise the bow.
We notch the arrow at eye height.
Hooking it to the drawstring.
It's quite a long bow, as you can see.
Ok.
The hand down here.
We look at the target.
Check the bow is OK.
And then we hook the thumb part of our glove on the drawstring here.
Then we grip the bow here, but as I said, you've got to be careful not to grip the bow
too tight.
It basically just rests in your hand, and as you turn it, it pulls the skin in your
fingers.
Ok?
So, we raise the bow up.
I'm supposed to be looking at the target, but I'm looking at the camera.
You raise the bow up.
Then first we turn our hand.
And then if you can see, but right now I don't need my fingers here, the bow is just resting
in the crook between my thumb and my forefinger.
Ok?
We pull the arrow down.
And it should be resting about your mouth height.
And then as I fire, the bow should rotate.
And that's it.
That's how you fire a Japanese arrow.
If I play that in slow motion, you might be able to see it. I'll try.
Anyway, thanks for watching.
Don't forget, if you look at the About section down here, you can find the link to the script
for this, and questions and answers.
You can practice listening, your writing, your reading, and even your speaking if you
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Have a nice day.
Bye.
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