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WHAT ARE CELLS MADE OF?

How did one travel earlier?


How did one travel earlier?

In the stone ages man shifted from one place to another only when the food at the first location became scarce. Families carried their possessions with them with the help of dogs and other animals. In regions with abundant water simple boats were made for transportation. After the invention of the wheel, new possibilities of transportation came up. Invention of carriages, wagons and later cars made travelling easier and faster. The only requirement was a network of roads.

 






How did the North American Indians carry their possessions?

 The original inhabitants of America frequently lived in the prairies. Since there were no roads in the prairie, vehicles with wheels could not be used easily. In addition, the wheel came to the American continent only with the vehicles of the European settlers. The native Indians used a travois for transportation: a triangle made of two long rods ties at one end and a crossbar at the other end. Over this a piece of leather or fabric was stretched to carry load. For centuries, dogs pulled these vehicles.  Latter, the horses introduced by the Europeans took over this job.

 


When was the wheel invented?

It not exactly known when the wheel was invented. The Sumerians used the wheels about 5000 years ago in Mesopotamia. They first used it as a potter’s wheel, and a few centuries later as a wheel on carts. In their excavations in Northern and Western Europe, archeologists have found remains of discs from the Stone Age. The wheels of the Sumerians were wooden discs, which were fixed on an axis with spikes. The first wheels with spokes also originated in Mesopotamia. Around 2000 BC the Sumerians built these lighter wheels for their war chariots, as did the Egyptians around 1600 BC.

 

What did boats look like in the beginning?

The first boats were simple logs, which people carried over rivers and seas. These log boats were made from a hollowed-out tree trunk for a safer journey. A long road was used initially, and latter a paddle was used for controlling boats. In regions without trees, boats were made out of other materials. The Indians made their boats from birch bark and the Eskimos made them from animal hides and leather. In southern Pacific, the coastal inhabitants used outrigger canoes about 5000 years ago. They had laterally placed floats, which made the boats more stable and faster.

 


What built the first network of roads?

The first network of roads was built by the Romans who were experts in road building. More than 2000 years ago they planned and built a network of roads which covered the entire Roman Empire and made every corner of it accessible. Messengers, traders and government officials-mainly soldiers-travelled on these roads between the capital city of Rome and the provinces. At the end of 4 BC, the roman roads were fortified so that the heavy war chariots of the generals could also travel n them. But gradually deep furrows started appearing on the pavement, and the chariots used to move as if on rails.

 

 

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