Men were already making ropes 35,000 years ago

Men were already making ropes 35,000 years ago

Most traditional ropes have three or four strands or strands. They are ancient and cosmopolitan: remains of these ropes have been found in Herculaneum (79 AD) and in the Egyptian port of Mersa, and date back to the Middle Kingdom (2033 to 1786 BC); It was also used by the Incas to weave suspension bridges. Therefore, the principle of manufacturing traditional ropes must have been known for a long time. Nicolas Conard, of the University of Tübingen, and Verl Rötz, of the University of Liège, have shown that an artifact dating back to the Swabian Aurignacian period (40,000-34,000 before present, or AP) was used to make four-strand ropes. !

On the right is a Roman marine rope discovered in Herculaneum. On the left is an Egyptian marine rope that was discovered in the port of Marsa.

plz/f. Savatier

Radiocarbon dating to between 35,000 and 40,000 years ago, the object in question was excavated in 2015 from the AH Va layer, in the Hohle Fels cave, located in the Ach Valley, in Baden-Württemberg. Once the thirteen parts were reassembled, a piece of mammoth tusk with four holes emerged. Many examples of perforated sticks are known from various periods of the Upper Paleolithic (50,000 to 11,800 AD), a period of expansionH. sane In Eurasia. In addition, several Swabian Aurignacian perforated sticks have already been found, in particular four in 1983 in Geissenklösterle cave, which have been interpreted as a work of art… Added to this are the three already discovered in 1931 in Geissenklösterle cave . Vogelherd, located in the Lune Valley, in the same area, which were then interpreted as lozenges, i.e. blades used to make a buzzing sound when rotated at the end of a rope.

After closely studying Aurignacian Swabian perforated sticks, Nicholas Cunard and Verl Roots came up with the hypothesis that these tools – all of roughly the same age – were used to make rope. They then closely studied those found in Hohle Fels, discovering under a microscope small fragments of plant fibers still attached to the dentin. It has four approximately circular holes 7 to 9 mm in diameter and aligned at a distance of 2 cm from each other. These holes were made with a flint blade in order to provide them with bundles of V-shaped grooves spiraling into the holes, as if to facilitate the passage of a roll of fibrous material. The same grooves are found on the Geissenklösterle's perforated stick.

Hohle Fels perforated stick of braiding rope

In A, a perforated Hohle Fels stick. In case (b), plant tissue remains were detected on the dentin by light microscopy. In C, a possible raw sap duct (trachea) was detected on the dentin by light microscopy. From D to K, the openings of the grooves can be seen close up.

e. Jensen, University of Tübingen/Dr. Knuts, University of Liège/F. Roots, University of Liège

To further convince themselves, the researchers reproduced one of the similarly perforated sticks, then used it to make ropes. To further convince themselves, the researchers reproduced one of the similarly perforated sticks, then used it to make ropes from strands made of twisted fibres. So they experimented with making yarn from deer sinew (fibrous) and flax (Line)Made from hemp (hemp),distv(Tifa, Or broad-leaved cattail, these aquatic plants are recognizable by their brown, ornamental tubes) in willows (Salex) Or even nettle (Urtica). Once they were sure that the Aurignacians could find them in nature, they focused on—probably—the most common of them all: cattails.

Aurignaceae braiding rope

Researchers create a rope from fibrous cattail leaves using a replica of the tool discovered in Hohl Fels Cave.

V. Roots, University of Liège

They then tested the following procedure: While one experimenter inserted bundles of fibrous and lamellar cattail leaves by a spiraling motion into the perforated holes of the stick, after twisting them, another grabbed the object and pulled it towards him to make the bundles move; These, twisted, then automatically form the rope behind the body. Regulated notch openings allow maintaining a uniform thickness of filaments and facilitate extending the bundles with new rolls of sheets. The grooves help break up the leaves with unnecessary soft parts, guiding the fibers during twisting. By pulling the tool back steadily to create tension, an even rope is produced. Thus, the researchers came to the conclusion that ten minutes are enough to obtain 5 meters of flexible rope with the familiar appearance of four-strand ropes. They also concluded that the use of a perforated stick is not necessary for thin ropes, which are easier to obtain by hand.

Thus we find the same shape familiar to traditional strings since the Aurignacian period. Why is this constant? When sufficient and regular, wrapping the rope with three or four strands distributes the forces necessary for resistance evenly over the entire section of the rope. This makes the rope capable of withstanding much greater tension than the total tension each rope can withstand. But to obtain this result, the friction between the threads must prevent any rotation of one of them in one direction or another. However, in 2010, Jacob Bohr and Casper Olsen, of the Technical University of Denmark in Lyngby, demonstrated that for purely engineering reasons, the number of revolutions that can be made no Flexible cylindrical filaments together form multiple helices with a given length up to a maximum. In other words, when manufacturing a given length of rope, there is an optimal number of turns ensuring the greatest length of contact between the strands, and thus the greatest possible friction. According to Jacob Bohr and Casper Olsen, this optimal number is about 32 turns per meter for a three-strand rope, the length of which would then be equal to 68% of the length of the strands; It is about 25 turns per meter for a length of four-strand rope, whose length will then be equal to 69% of the length of the strands. The reasoning done by Jacob Bohr and Casper Olsen leads them to conclude that, provided the strings are in tension, we naturally arrive at an almost perfect rope. That is why, since the Aurignacian period and everywhere on Earth, ropes with three or four strands have had the same appearance!

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