Top 5 Lost Technologies

5. Damascus Steel

Damascus steel was an impossibly strong type of metal that was widely used in the Middle East from 1100-1700 AD. It is most famously associated with swords and knives. 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. The blades are believed to have been created using wootz steel, which was most likely imported from India and Sri Lanka and molded and blended to create a patterned blade. The special quality of the swords is thought to have derived from this process, which weaved together tough cementite and soft iron to form a metal that was as strong as it was flexible.
How was it Lost?
The particular process for forging Damascus steel appears to have disappeared sometime around 1750 AD. The exact cause for the loss of the technique is unknown, but there are several theories. The most popular is that the supply of ores needed for the special recipe for Damascus steel started running low, and sword makers were forced to develop other techniques. Another is that the whole recipe for Damascus steel—specifically the presence of carbon nanotubes—was only discovered by accident, and that sword smiths didn’t actually know the technique by heart. Instead, they would simply forge the swords en masse, and test them to determine which met the standards of Damascus steel. Whatever the technique, Damascus steel is one technology that modern experimenters have been unable to fully reproduce. There are pattern welded knives that are marketed as being made from “Damascened steel”, but while usually well made, they are only approximations of the lost technique for real Damascus steel.
4. Apollo/Gemini Space Program Technology


Not all lost technology dates back to antiquity—sometimes it’s just become so obsolete that it’s no longer compatible. The Apollo and Gemini space programs of the 50s, 60s, and 70s were responsible for NASA’s biggest successes, including some of the first manned space flights and the first trip to the moon. Gemini, which ran from 1965-66, was responsible for the much of the early research and development into the mechanics of human space flight. Apollo, which followed shortly thereafter, was launched with the goal of landing a crew on the surface of the moon, which it succeeded in doing in July of 1969.
How was it Lost?
The Apollo and Gemini programs aren’t truly lost. There are still one or two Saturn V rockets lying around, and there are plenty of parts from the spacecraft capsules still available. But just because modern scientists have the parts doesn’t mean they have the knowledge to understand how or why they worked the way they did. In fact, very few schematics or records from the original programs are still around. This lack of record keeping is a byproduct of the frenetic pace at which the American space program progressed. Because NASA was in a space race with the USSR, the planning, design, and building process of the Apollo and Gemini programs was always rushed. Not only that, but in most cases private contractors were brought in to work on every individual part of the spacecraft. Once the programs ended, these engineers—along with all their records—moved on. None of this would be a problem, but now that NASA is planning a return trip to the moon, a lot of the information about how the engineers of the 1960s made the voyages work is invaluable. Amazingly, the records remain so disorganized and incomplete that NASA has resorted to reverse engineering existing spacecraft parts that they have lying around in junkyards as a way of understanding just how the Gemini and Apollo programs managed to work so well.
3.  Silphium

Lost technologies aren’t always the result of too much secrecy or poor record keeping—sometimes nature just doesn’t cooperate. This was the case with Silphium, an herbal wonder drug that the Romans used as one of the earliest forms of birth control. It was based on the fruit of a particular genus of the fennel plant, a flowering herb that only grew along a certain shoreline in modern day Libya. The heart-shaped fruit of the Silphium plant was known to be something of a cure-all, and was used to treat warts, fever, indigestion and a whole host of other ailments. But it was Silphium’s powers as a contraceptive that made it one of the most valuable substances in the Roman world, to the point that the plant appears on several different pieces of ancient Roman currency. Women would drink Silphium juice every few weeks, and this would be enough to prevent pregnancy. Using the herb would even terminate an existing pregnancy if used correctly, which would make Silphium one of the earliest methods of abortion.
How was it Lost?
Silphium was one of the most sought after drugs of the ancient world, and its use spread rapidly across Europe and into Asia. But despite its remarkable effects, the particular genus of plant needed would only grow in one area along the Mediterranean in North Africa. Its scarcity, combined with an overwhelming demand, more than likely led to over harvesting, which drove the plant into extinction. Because the particular species no longer exists, modern scientists are unable to examine Silphium to see if its powers of contraception were really as effective as Roman historians and poets would lead one to believe, or if there were any adverse side effects. Still, it is worth noting that other herbs that are chemically similar to Silphium have been proven to have a fairly high rate of preventing pregnancy.
2. Roman Cement

Modern concrete was developed in the 1700s, and today the simple mixture of cement, water, sand, and rocks is the most widely used building material in the world. But the recipe developed in the 18th century wasn’t the first time concrete was invented. In fact, concrete was widely used throughout antiquity by the Persians, Egyptians, Assyrians, and Romans. The Romans in particular made extensive use of concrete, and they were responsible for first perfecting the recipe by mixing burnt lime with crushed rocks and water. Their mastery of its use allowed them to build many of their most famous structures, among them the Pantheon, the Colosseum, the aqueducts, and the Roman Baths.
How was it Lost?
Like so many technologies of the Greeks and Romans, the recipe for concrete was lost during the descent into the Dark Ages, but just why remains a mystery. The most popular theory is that the recipe was something of a trade secret among stonemasons, and that the method for making cement and concrete died along with those who knew it. Perhaps even more interesting than the disappearance of Roman cement are the particular qualities that separate it from more modern Portland cement, which is the most common type of cement used today. Structures built with Roman cement, like the Colosseum, have managed to weather thousands of years of punishment from the elements and remain standing, but buildings constructed with Portland cement have been known to wear down much faster. This has been theorized to be the result of different chemicals that the Romans added to their cement, among them milk and even blood. These were said to create air bubbles within the concrete that helped the material to expand and contract in the heat and cold without damaging itself.
1. Greek Fire

Perhaps the most famous of all lost technologies is what is known as Greek Fire, an incendiary weapon that was used by the military of the Byzantine Empire. A primitive form of napalm, Greek Fire was a kind of “sticky fire” that would continue burning even in water. The Byzantines most famously used it during the 11th century, when it was credited with helping to repel two sieges of Constantinople by Arab invaders. Greek Fire could be deployed in many different ways. In its earliest form it was poured into jars and thrown at enemies like a grenade or a Molotov cocktail. Later, giant bronze tubes were mounted on warships, and siphons were used spray the weapon at enemy vessels. There was even a kind of portable siphon that could be operated by hand in the style of a modern flamethrower.
How was it Lost?
The technology behind Greek Fire certainly isn’t completely alien. After all, modern militaries have now been using similar weapons for years. Still, the closest counterpart to Greek Fire, napalm, wasn’t perfected until the early 1940s, which would mean the technology was lost for several hundred years. The weapon’s use seems to disappear after the decline of the Byzantine Empire, but just why still isn’t known. Meanwhile, the possible chemical composition of Greek Fire has been widely studied by historians and scientists. An early theory was that the mixture included a heavy dose of saltpeter, which would make it chemically similar to gunpowder. This idea has since been rejected, because saltpeter wouldn’t burn in water. Instead, modern theories propose that the weapon was more likely a cocktail of petroleum and other chemicals, possibly including quicklime, niter, or sulfur.
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