From the first explosion of Mongol military might from the steppes of central Asia in the early decades of the 13th century to the death of Timur inthe nomads of central Asia made a last, stunning return to center stage in world history.
Cargo tramways can be fully or partly powered by gravity, and some deliver excess power that can be utilized to generate electricity or to drive cranes or machinery in nearby factories. Some innovative systems have been constructed in recent years.
In a monocable system, one endless rope serves to both support and move the carriers in transit. In a bicable or tricable system, separate ropes sustain these history of catapults essay help Ancient and medieval ropeways were of both variety, while modern ropeways from the s onwards were initially exclusively monocable systems.
Later, bicable systems took over almost completely. At the end of the 19th century, both ropeway methods were also applied to canal transportation see the article on trolley canal boatswith monocable systems used for cable trains.
If only one endless rope would be used on a track which includes a long span or a steep grade, it would become necessary to make the entire double length of the moving rope strong enough for the special strain that appears on that spot. Increasing the size of the rope affects the dimensions of the supports, sheaves and other fixtures throughout the line, adding to the costs.
In a bicable system, the stationary carrying cable can be locally graduated to the strains it has to bear. Ropeways in ancient times Ropeways have been used for more than 2, yearstransporting both passengers and goods.
The first sign of their use comes from the rugged Asiatic countries of China, India and Japan, where it is speculated that they may have been in operation since BC. Men used rope to cross ravines, rivers and river-gorges, initially transferring themselves, hand over hand, with the body suspended by a crude harness.
The harness eased the load and allowed a rest as the loop was slid along the rope track. The next application was to pull oneself back and forth in a basket or cradle, usually with a few belongings in tow. This was made possible by means of thinner cords fixed to the front and the back of the basket, or by gravity in case the arrival point was at a lower height than the starting point.
The empty sling or basket was then drawn back to its original position by a smaller cord attached to the back as before. Sometimes, the rope was threaded through a hollow piece of bamboo before being attached, so that the person could slide down the rope without burning their hands.
All that was needed to build a ropeway was a ropeknots to tie the rope to a rock or tree or anchor on both sides, and a bow and arrow to shoot the rope across. After the invention of the crossbow by the Chinese, heavier cables could be shot over longer distances.
Sometimes the rope was supported on simple wooden trestles. Ropeways were also used to transport pack animals. Inversely, pack animals were sometimes used to pull the ropeway. These early aerial ropeways were the forerunners of later technologies such as the suspension bridge and the elevator.
They were also the closest approach to aerial navigation at the time. Ropeways in the Middle Ages One of the first mention of ropeways in medieval times appears in the "Taiheiki", a Japanese historical epic written in the late 14th century.
It relates how a Japanese emperor escaped via ropeway over a valley when surrounded by enemy forces. In Europe, initial reference to the use of ropeways can be found in Bellifortis, a weapons catalogue from A book is the first to show a drawing of a ropeway.
Between andwhen technologies such as water millswindmills and harbour cranes became increasingly popular, references to both monocable and bicable operations increased.
In South America, aerial ropeways to transport gold have been reported as far back as The 17th century saw an increase in design sophistication. Venetian Fausto Veranzio illustrated a refined bicable passenger ropeway in the "Machinae novae", published in and It consisted of a wooden box in which the passengers rode, travelling on pulleys over a fixed rope second picture from the start.
The vehicle was propelled over the river by the occupants pulling themselves along by means of this slack loop. Dutchman Wybe Adam erected a successful large-scale operational system inwhich is described in the Danzig Chronicles picture introduction and picture below.
Ropeways were also constructed by monasteries built high on pinnacles, where they were used to lift supplies and visitors. Ropeways from the s onwards From about tono further progress was made.
The technology had reached its maximum potential at the time, limited by the strength of the available ropes.A collection of scholarly works about individual liberty and free markets. A project of Liberty Fund, Inc. Facsimile PDF MB This is a facsimile or image-based PDF made from scans of the original book.
Kindle KB This is an E-book formatted for Amazon Kindle devices. EBook PDF KB This. These days, we use them almost exclusively to transport skiers and snowboarders up snow slopes, but before the s, aerial ropeways were a common means of cargo transport, not only in mountainous regions but also on flat terrain, with large-scale systems already built during the Middle Ages.
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