Evolution of Transport
Before the invention of the wheel, the only means of transportation was walking. For transporting goods, people used animals like donkeys, horses, mules, elephants, oxen, sled dogs, and even bison. Boats were also used as a means of transportation on water. The earliest boats were simple logs of wood with a hollow cavity.
The oldest wheel was discovered in Mesopotamia, and is believed to be over 5,500 years old. Fixed wheels for carts were invented around 3500 BC, according to some historians. After the invention of the wheel, man started using animals to pull vehicles that moved on wheels, and thus, bullock carts and chariots came into existence. Till the 19th century, most forms of transport used only animals
The bicycle was invented in the late 18th century bicycles. The first bicycles did not have brakes, though. It was up to the rider to the control the speed of the bicycle! Later on, motors were fitted to bicycles, and thus, mopeds came into existence. Further research and development led to the invention of the motors car.
The steam engine and the rail road were invented in the 19th century. Apart from these, motorised boats and ships were used as a means of water transport. Roads, rail road and water remained the major means of transport for a very long time. The Wright brothers invented the airplane and gave the world another means of transport – airways. In his effort to explore his universe, man even stepped into space and invented the spaceship to travel in space.
There are various means of transport, such as road, rail, water and airways. The mode of transport can be chosen, usually depending upon the distance to be travelled, but sometimes also upon how fast you want to get to your destination.
Measuring Length and Distance
Various means of measurement, such as the palms, fingers, arm length and feet, were used to measure length and distance before standardised systems were introduced. Standards needed to be set to ensure consistency and to standardise measurements. Several systems were devised, but almost the entire world now follows the metric system.
The base measurement for the pyramids is the cubit, which was formulated by the Egyptians. A cubit was measured on the arm, from the point where the elbow bends, to the tip of the middle finger. One cubit is equal to 18 inches. However, the inch was invented by the Romans.
In order to avoid confusion in measurements, the French created in 1970 the metric system, which is a standard for measurement. A further development to ensure uniformity measurement of lengths and distances, and other quantities, was a standard of measurement called the International System of Units or SI.
The SI unit of length is the metre, and is denoted by the small letter ‘m’. This is the basic unit of length.
1 metre =100 centimetres
1 centimetre=10 millimetres
10 millimetres=1 centimetre
Large distances are measured in kilometres, and 1 km=1000 m.
The length and type of an object determines the kind of measuring tool one can use.