5 lost technologies from different times
Despite the fact that the modern world is one of the technological development of the peaks, not all knowledge of the past have survived. Actually, it seems as if some of the invention have been lost, but some of the old technology are incomprehensible to his contemporaries. Below, your attention is invited to the five lost technology, which still attract the attention of scientists.
Modern concrete is a mixture of cement, water and aggregates such as sand or gravel, it was invented at the beginning of the XVIII century, and is the most common building material in the world today. However, a compound developed in the XVIII century, is not the first concrete views. In essence, the concrete used Persians, Egyptians, Assyrians and Romans. Recent added to the developer mixture burnt lime, crushed stone, and water - that this composition gave Rome Pantheon, Colosseum, aqueducts and terms.
Like many other ancient knowledge, this technology has been lost with the advent of the Middle Ages - it is not strange that this historical period is also known as the Dark Ages. According to the popular version, which explains the fact of the disappearance of the recipe, it was something of a trade secret, and with the death of those few people who were devoted to her, he was forgotten.
It is noteworthy that the components that distinguish the Roman cement from the present, are still unknown. Buildings erected using Roman cement, stood Goals, despite exposure to the elements - cement used nowadays, can not boast such resistance. Some historians believe that the Romans added milk and blood in the mortar - it is assumed that the pores that were formed through this process, allow the composition to expand and contract under the influence of temperature changes, while not collapsing. However, the strength of the cement gave other substances, but no one can say exactly what it is.
Damascus steel, extremely durable type of metal, widely used in the Middle East in about 1100-1700 years BC. Basically, this type of steel has become known thanks to the swords and knives that were made out of it. Blades are forged from Damascus steel, famous for their strength and sharpness: it was believed that the sword of Damascus could easily cut stones and other metals, including armor and weapons made of weaker alloys.
Damascus steel is associated with patterned tiglevoy steel from India and Sri Lanka. The high strength of such steel blades explained the manufacturing process in which the hard cementite mixed with slightly more soft iron, whereby products were obtained at the same time strong and flexible.
Damascus steel forging technology was lost around 1750. The exact reasons as to why this happened is unknown, but there are several versions, one way or another to explain those reasons. The most popular theory is that the ore needed for the production of Damascus steel, began exhaustive and gunsmiths were forced to switch to alternative technologies for the production of blades.
According to another version, blacksmiths, and did not know the technology - they simply forged many blades and tested them for strength. It is assumed that by coincidence, some of them were properties characteristic of Damascus. Be that as it may, even at this stage of development of technology it is impossible to precisely restore the process of creating Damascus steel. Despite the fact that the blades with a similar pattern exists in our days, to achieve the strength of Damascus steel modern masters, all the same, can not.
One of the most mysterious archaeological finds Antikythera mechanism was found by divers on the sunken ancient ship near the Greek island of Antikythera in the early twentieth century. Study the following shipwreck, scientists have concluded that the ship dates from the I and II century BC. At the same time, the mechanism was found extremely complicated in its structure: it consisted of more than 30 gears, levers and other components.
Furthermore, it uses a differential gear, which, as previously thought to have been invented until the XVI century. Obviously, the device was designed to measure the position of the Sun, the Moon and other celestial bodies. Describing this mechanism, some experts refer to it as the original form of mechanical watches, while others consider it the first known analog computer.
The accuracy with which the components of the mechanism have been met, indicating that the device was not the only one of its kind. On the other hand, the historical record of the mechanisms whose structure resembles the find dates back to the XIV century, which means that for more than 1400 years the technology was lost.
Greek fire, combustible mixture used for military purposes by the Byzantine Empire and other states - this is one of the most famous of the lost technology. Being something of the original form of napalm, Greek fire continued to burn even in the water. The most famous case of this formidable weapon took place in the XI century, when Byzantines used fire against Arabs and plunged them to flight.
At first, the Greek fire was poured into small vessels that burned and hurled at the enemy, like the modern Molotov cocktail. It was later invented installation, consisting of a copper pipe with a siphon - these combat vehicles were used to set fire to enemy ships. In addition, there is information about manual installation, vaguely reminiscent of modern flamethrowers. Of course, our time, the armed forces use combustible mixture and, therefore, can not be said that the technology remains completely unknown. On the other hand, napalm was developed only in the 40s of the twentieth century, and the original composition of Greek fire was lost after the fall of the Byzantine Empire - so efficient technology, nevertheless, remained lost for centuries. So far it is difficult to say exactly how faded the substance. In addition, scientists do not know what could be used to prepare the mixture.
According to the earlier version, the Greek fire would include a large dose of nitrate. However, this version was soon abandoned, because nitrate is not lit in the water, and it is this property attributed to the Greek fire. If you believe a new theory, it was a such a combustible cocktail of petroleum or crude oil, as well as burnt lime, potassium nitrate, and possibly sulfur.
Technology program "Apollo" and "Gemini"
It turns out that not all the lost technology originated in ancient times - even relatively recent advances in science and technology may be incomprehensible to his contemporaries. In the 50s, 60s and 70s of the twentieth century space program "Gemini" and "Apollo" has led to the most notable achievements in the field of human spaceflight. In particular, we are talking about the major successes of NASA, namely, the program "Apollo 11" and the landing of man on the moon. In turn, the earlier program "Gemini" 1965-66. given scientists valuable knowledge about the mechanics of flight in space.
Of course, the achievement of program "Gemini" and "Apollo" can not be considered to be lost in the traditional sense of the word, because at the disposal of scientists are still in the carrier rocket "Saturn 5", as well as fragments of other spacecraft. On the other hand, possess mechanisms still does not imply knowledge of the technology. The fact is that as a result of high rates of "space race" documentation was not as good as desired date of NASA employees. In addition to hurry, the situation is aggravated by the fact that for the preparation of programs hire private contractors working on the individual components of ships and equipment. Once the programs have been brought to completion, private engineers left, taking along their drawings and diagrams. As a result, now that NASA is planning a new mission to the moon, large amounts of the required information are unavailable or are in absolutely chaotic state. In essence, all that remains of NASA, under the circumstances, is to appeal to reverse engineering, that is, to the analysis of existing ships.