A colourless, odourless, non-reactive gas, it constitutes 78.1% of Earth´s atmosphere.
Members of the ancient Roman Legions were the masters of military tactics.
The phalanx formation was a military formation of the Greek heavy infantry.
During World War I, Britain was part of the military alliance called the ´Triple Entente´.
The surface of a sphere consists of the set of points which are all at the same distance...
Calculating the volume of a sphere is possible using an appropriate cylinder and cone.
This animation demonstrates the construction of a fire engine.
The Votive Church of Szeged, located on the Great Plains of Hungary, emerges from the...
The animation demonstrates how laser printers work
A medieval glider constructed by Abbas Ibn Firnas.
The saker falcon is a large bird of prey widespread in Europe and and Asia.
This animation compares a modern living room and a typical bourgeois salon.
This animation demonstrates the structure of water towers.
The most important types of local winds are the sea-land breeze, the mountain-valley...
Alkanes are saturated hydrocarbons which can be organised into a homologous series.
This animation demonstrates the development of freight transport, from horse-drawn carts...
The structure of fortresses developed together with military technology.
Change of light conditions in different seasons. Measuring height using shadows.
A prehistoric amphibian and an early representative of the Tetrapods, which became...
Қазақстанда, Есік қорғанынан қазба жұмыстары кезінде ретінде белгілі доспехи жауынгер,...