Despite the fact that the modern world is on one of the peaks of technological development, scientists note that not all knowledge of the past has reached our days. Actually, it seems that some inventions have been lost, and some old technologies are incomprehensible to contemporaries. Below you are offered five lost technologies, which still attract the attention of scientists.
Modern concrete, which is a mixture of cement, water and aggregates, such as sand or gravel, was invented in the early 18th century and is the most common building material in the modern world. However, the composition, developed in the XVIII century, is by no means the first kind of concrete. In fact, concrete used Persians, Egyptians, Assyrians and Romans. The latter added to the building mix quicklime, crushed stone and water – this particular composition gave Rome the Pantheon, the Colosseum, the aqueducts and the thermae.
Like many other knowledge of antiquity, this technology was lost with the onset of the Middle Ages – it is not strange that this historical era is also known as the Dark Ages. According to the popular version, explaining the fact of the disappearance of the recipe, it was something of a commercial secret and with the death of those few people who were devoted to it, it was forgotten.
It is noteworthy that the components that distinguish Roman cement from the modern, still remain unknown. The buildings erected with the use of Roman cement stood for millennia, despite the impact of the elements – cement, used in our time, can not boast such steadfastness. Some historians believe that the Romans added milk and blood to the building mix – it is assumed that the pores formed due to this process allowed the composition to expand and contract under the influence of temperature changes, while not breaking down. However, the strength of the cement was crushed by other substances, but no one can say exactly which ones.
Damascene steel, an incredibly strong type of metal, was widely used in the Middle East in about 1100-1700 AD. Basically, this kind of steel became known thanks to the swords and knives that were made of it. Blades forged from Damascus steel were famous for their strength and sharpness: it was believed that a sword from Damascus could easily cut stones and other metals, including armor and weapons made from weaker alloys. Damascus steel is associated with patterned crucible steel from India and from Sri Lanka. The high strength of the blades from such steel was explained by the production process, during which the hard cement was mixed with a slightly softer iron, resulting in the products being simultaneously strong and flexible.
The technology of forging damask steel was lost in about 1750. The exact reasons why this happened are unknown, but there are several versions that somehow explain these reasons. The most popular theory is that the ore required for the production of Damascus steel began to be exhausted and the armourers were forced to switch to alternative technologies for the production of blades.
According to another version, blacksmiths themselves did not know the technology – they simply forged a lot of blades and checked them for strength. It is assumed that, at random coincidence, some of them received properties characteristic of Damascus. Whatever it was, even at the current stage of technology development, it is impossible to accurately restore the process of creating Damascus steel. Despite the fact that blades with a similar pattern exist today, to achieve the strength of Damascus steel modern masters, yet, not in the force.
One of the most mysterious archaeological finds, the Antikythera mechanism, was found by divers on a sunken ancient ship not far from the Greek island of Antikythera in the early 20th century. After studying the shipwreck trails, scientists came to the conclusion that the ship dates from the 1st and 2nd centuries BC. At the same time, the found mechanism was incredibly complex in its structure: it consisted of more than 30 gears, levers and other components.
Moreover, it used a differential transmission, which, as was supposed earlier, was invented no earlier than the 16th century. Apparently, the device was intended to measure the position of the Sun, Moon and other celestial bodies. Describing this mechanism, some experts call it the original form of a mechanical clock, while others consider it the first known analog computer.
The accuracy with which the components of the mechanism were performed indicates that the device was not unique in its kind. On the other hand, historical records of mechanisms, whose structure resembles the find, date back to the XIV century, and therefore, for more than 1400 years, technology has been lost.
Greek fire, a combustible mixture used for military purposes by the Byzantine Empire and other states, is one of the most well-known lost technologies. Being somewhat like the original form of napalm, Greek fire continued to burn even in the water. The most famous use of this formidable weapon took place in the XI century, when Byzantium used fire against the Arabs and fled them.
At first Greek fire was poured into small vessels, which were set on fire and thrown into the enemy, like a modern Molotov cocktail. Later, installations consisting of copper pipes with a siphon were invented – these fighting vehicles were used to set fire to enemy ships. In addition, there are data on manual installations remotely resembling modern flamethrowers.
Of course, the armed forces of our time use combustible mixtures, which means that we can not say that the technology remains completely unknown. On the other hand, napalm was developed only in the 40s of the 20th century, and the original composition of Greek fire was lost after the decline of the Byzantine Empire – thus, effective technology, however, remained lost for several centuries. It is still difficult to say exactly how the composition of the substance was lost. In addition, scientists do not know what could be used to prepare the mixture.
According to the earliest version, Greek fire could include a large dose of saltpeter. However, this version was soon rejected, because saltpeter does not burn in water, but this property was attributed to the Greek fire. If you believe a newer theory, the fuel was a kind of cocktail of oil products or crude oil, as well as quicklime, potassium nitrate and, possibly, sulfur.
Technologies of Apollo and Gemini
It turns out that not all the lost technologies originated in antiquity – even the relatively recent achievements of science and technology can remain incomprehensible to contemporaries. In the 50s, 60s and 70s of the 20th century, the space programs “Gemini” and “Apollo” led to the most visible achievements of mankind in the field of space flights. In particular, we are talking about the greatest success of NASA, namely, the Apollo 11 program and the landing of a man on the moon. In turn, the earlier Gemini program of 1965-66. gave scientists valuable knowledge about the mechanics of flying into space.
Of course, the achievement of the Gemini and Apollo programs can not be considered lost in the traditional sense of the word, because the scientists still have the Saturn 5 rockets and fragments of other spacecraft. On the other hand, the possession of mechanisms does not yet imply knowledge of technology. The matter is that as a result of high rates of “space race” the documentation was conducted not so well, as would like modern workers of NASA. In addition to haste, the situation is aggravated by the fact that private contractors working on individual components of ships and equipment were hired to prepare the programs.
After the programs were brought to completion, the private engineers left, taking with them their drawings and diagrams. As a result, now that NASA plans a new flight to the moon, large amounts of necessary information remain inaccessible or are in an absolutely chaotic state. In essence, all that remains of NASA in the circumstances is to turn to reverse engineering, that is, to analyze the existing ships.