(mysterious flute music)
- [Voiceover] The Byzantine Empire
once discovered a formula
for a powerful naval flamethrower.
It was even reported that the mysterious Greek fire
was easily transported,
could burn on water,
and set ships ablaze from long range.
The closest modern equivalent to Greek fire is napalm,
but it has been speculated that the properties of Greek fire
may even be superior to the best napalm we have today.
The trouble is that the formula for Greek fire
was a very closely guarded secret,
and with the fall of the Byzantine Empire,
the formula was lost to history.
Damascus steel was an impossibly strong type of metal
that was forged in the Middle East in the 1100s.
Blades forged with Damascus steel
were known for their amazing strength and cutting ability,
and were said to be able to slice rocks and other metals,
including the blades of weaker swords,
cleanly in half.
Careful examination of surviving Damascus steel swords
reveals that they actually contained carbon nanotubes,
which gives them their strength.
Unfortunately, however, the Damascus formula
was lost around the year 1750,
and then simultaneously,
the supply of unique ores
needed to create Damascus steel ran out.
As a result, sword makers were forced
to develop other techniques,
and after a few centuries,
the secret process to create the steel was lost.
So far, modern experiments have been unable
to fully reproduce Damascus steel.
Modern concrete was actually developed in the 1700s
and is the most widely-used building material in the world.
But this recipe for concrete
wasn't actually the first time concrete was invented.
In fact, a different form of concrete
was widely used throughout antiquity
by the Persians, Egyptians, and Romans.
The Romans in particular made extensive use of concrete,
and they were responsible for first perfecting the mixture.
In fact, their concrete was so sturdy
that many of their structures still stand to this day.
But like so many technologies of the Greeks and Romans,
the Roman recipe for concrete was lost
during the descent into the Dark Ages.
This is very disheartening,
because while Roman concrete stands for thousands of years,
modern concrete often is weathered down within a century.
Some of the technology
that the Greeks and Romans had access to
surpasses even the greatest advancements of the modern age.
One great example of this is nepenthe,
which was a primitive anti-depressant
that was known for its ability to chase away sorrow.
The drug is frequently mentioned
in Greek and Egyptian writings,
but no one really knows how to make this medicine.
It's likely that the formula has been lost to history
and that the plants used to create it
have since gone extinct.
Today, the world is desperately in need
of a cure for depression,
as millions of people are afflicted by it around the globe.
The closest substitutes we have today
are various synthetic compounds and opium,
but none of these even come close
to the described effectiveness of nepenthe.
During the earliest days of computers and the internet,
the Dutch computer engineer Jan Sloot
allegedly invented a vast data compression technique.
Sloot claimed that his technique
could compress an entire movie file,
which would be about 10 gigabytes,
into just eight kilobytes,
with no loss in quality.
When Sloot offered to sell his technique
to various technology firms
during the dot-com boom of the 1990s,
most companies were skeptical.
Except for one.
Philips Electronics.
Philips was so impressed by Sloot's data compression system
that they rushed in to sign a contract with him.
Unfortunately, the day before Sloot signed,
he was struck by a heart attack and never recovered.
Sloot's business partners tried to move forward
with the technology anyways,
but a key floppy disk that contained the code
for the data compression system
was lost and never recovered.
If Sloot's data compression system had been used,
it's likely that the very face of the internet and computers
would be radically different,
as even the best solid-state drives of today
would pale in comparison to the storage capacity
of Sloot's system.
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