Around 600 BC Thales of Miletus
widely regarded as the first Greek philosopher.
As he was the first to be purely natural explanation
of the phenomena he observed. A key observations
he made was that certain stones such as amber
when rubbed against fur would exhibit a strange
property. The amber seem to emit an invisible force
which would attract small fibers.
And he assumed that this rendered amber magnetic another force he observed when
playing with lodestone
which are naturally-occurring magnets. Many after him observed that the
contact or friction with fur seem to create an imbalance.
Something was pulled from the fur and transferred onto other objects.
Now, not only did this result in a small attractive or repulsive force
but also in the potential for shocks to occur.
Once the discharge occurred the force disappeared.
So the shock with some form of discharge which reversed the imbalance created by
the friction.
Throughout history we're also fascinated with lightning bolts.
Nature's most passionate displays of power and aggression.
Most cultures assume this was a divine force
outside the reach of human hands and was therefore reserved for the gods.
Up until the 17th century, our descriptions of it varied from an
invisible, intangible, imponderable agent
or even threads of syrup which along gate and contract.
And it was Benjamin Franklin, who in 1752 set out to prove that there is a connection
between lightning and this tiny shocks due to friction.
In a famously dangerous experiment
done alone with his son, he let a kite into a thunderstorm and
near the bottom where the thread was wet,
he tied an iron key and after some time
he brought his knuckle up to the key experienced the series of small shocks
identical to the ones created by contact with fur.
This showed that indeed, lightning was simply the same thing is these household shocks
but on a massive scale. And at this time people have begun to divide materials
into two categories:
one were objects which would allow or accept discharge
such as gold or copper which we call electrical conductors.
Interestingly these materials are also generally good at conducting heat.
And number two were objects which would not allow this discharge such as
rubber or electrical insulators.
These materials also seem to insulate the transfer of heat
and we also began trying to measure this
force that Thales had encountered. One way to do this was to suspend the
piece of spongy plant called the pith ball from a thread
and when we're up in insulator against fur and brought it near the pith
ball it would pole on it
causing a deflection.
If we had more objects we noticed the fraction increased
due to a greater pulling force.
We also noticed that the shape of an insulators made a difference.
Large thin insulators seem to exhibit a much stronger force.
(soft bell ring)
And amazingly, it was found that conductors such as copper
wire would transmit this pulling effect over a distance.
This was demonstrated by running a long wire
between the pith ball in the charged insulator.
When the object was brought near the wire
it pulled through the wire and deflected the pith ball instantly.
When we later touched the wire with our finger
discharge occurs and the pulling stops and the ball is released.
Immediately people began speculating that this could be the future
optical telegraph. In 1774 French inventor George Louis Le Sage
was one of the first one to record actually set up this idea.
He sent messages through an array of 26 wires
each wire representing a letter of the alphabet. When a discharge occurred at
one end the pith ball would move at the other.
The trouble with this telegraph was that it only extended between the two rooms of his house.
The power the deflection was small and difficult to work with.
Though at the time people were investigating techniques for generating
larger charge differences
in order to amplified a force involved. One improvement
popularized by Alessandro Volta one year later
was an easy wave generating discharges on demand.
It was based on the idea that a charged insulator
could induce or transfer the charge onto a nearby
conducting plate. One needed to merely bring the metal plate close to the insulator
which would pull on the charge distribution in the metal plate
resulting in an imbalance or electrical tension in the metal plate.
Then want to bring their finger to the plate in it discharge would occur
then the plate is pulled away using insulating handle
and an access charge would remain trapped in the plate
to play could then be discharged at will simply by touching it to a conductors
such as a finger
and amazingly this process can be repeated many times without recharging
the insulating plate.
We could then generate many small discharges at will.
And by now Benjamin Franklin was focused on finding out how to trap or store up
these discharges.
At this time he still assumed that electricity with some sort of invisible fluid
Since we knew it could travel through water so we assume that
water inside in insulator could hold electricity.
What we now call the laid in jar was a glass jar
with water inside and a metal probe running at the top.
Franklin also wrapped the outside in a conductive metal.
When he brought a charge conductor towards the top probe
a discharge would occur and stay trapped in the jar.
More importantly was that the jar could be charged multiple times.
Each spark would amplify the charge separation
for electrical tension inside the jar. A good analogy is to think of the
jar as a balloon
and each discharge as a short jolt water.
And after 100 iterations the tension become massive.
And to release the charge
he simply touch the outside conductor
to the probe. A large discharge occurred.
Franklin improved the design over time
eventually realizing that the charge was not stored in the water
but glass. The water was merely a conductor path from the probe
to the jar. Today we would call the laid in jar a capacitor
or charge storing device. And when he changed many jars together he founded
increase the capacity even more and release deadly volt of electricity.
And over the years people focused on more effective ways a building up charge using
friction machines which could then be stored in capacitors
and relief the spectacular displays of man-made lightning.
And over the next 50 years people
tried to design systems for sending sparks
across greater distances using longer wires and more powerful discharges.
However sending electrostatic discharges as a communication method
seemed clumsy archaic and was no improvement over the existing
optical telegraph of the day.
They were widely ignored by government and industry.
Though the tides were rising.
An electric revolution was just around the corner.