The Moscow Kremlin

The Moscow Kremlin is the chief architectural ensemble of the capital. It has few rivals in the number of unique masterpieces of architecture and other art concentrated within its walls.

The might of these walls, its ridge-roofed towers and the three-dimensional expressiveness of the buildings clustered on its grounds offer panoramas of rare beauty. The triangle of the Kremlin walls, repeating the outline of Borovitsky Hill, encloses an area of 27.5 hectares. The maximum height of the hill above the level of the Moskva river is about 25 meters.

The ensemble of the Moscow Kremlin is the result of the efforts of many generations. Signs of a Slavic settlement here date to no later than the end of the 11^th century. At the time the fortress on the top of Borovitsky Hill covered an area of about 5 hectares. The first Moscow fortifications consisted of a moat, a rampart and a palisade. The city built here on the orders of Prince Yuri Dolgoruky in the 12^th century was 5 to 6 times as large as the initial area.

By the end of the 15^th century the unification of the Russian feudal principalities was completed and a United Russian State had been formed. Ivan the III the grand prince of all Russia launched reconstruction of the Kremlin on the large scale, having invited a number of master builders from Italy for the purpose. So the Italian architect and military engineer Aristotel Fioravanti arrived in Moscow to work there for many years.

The new Cathedral of the Dormition (1475-1479) was the first to be built. In 1484-1489 the festive Cathedral of Annuciation was erected next to it. They were joined by the Cathedral of the Archangel in 1505-1508.

For a whole decade starting from 1485 old walls and towers were replaced with new ones. It was then that the Kremlin acquired its present-day outlines.

The fortress walls forming an irregular triangle are of 2.235 m long, from 3.5to 6.5m thick and from 5 to 19 m high. Atop the walls stand 1,045 bifurcated merlons from 2 to 2.5 m long in height and fitted with narrow embrasures.

Along the east a moat 12 m deep and 32 m high surrounded kremlin walls.

On its northwest side Borovitsky Hill was protected by the Neglinnaya river and on its south side by the Moskva river.

The Kremlin was a superb example of the fortification art of the period.

Air-Conditioning

Air-conditioning is the bringing of air in a building to a desired temperature, purity and humidity throughout the year to maintain healthy and comfortable atmosphere.

Air-conditioning may be divided into two main sections: one for the processing of materials in industry; the other for human comfort. It has been found that there is an optimum condition of temperature and humidity at which the processing of different materials may be carried out with the minimum of wastage and the maximum of goods of specification quality. The system is therefore designed to produce air of predetermined temperature and moisture content and to keep it so despite all external influences. Such air is filtered free of foreign material.

Conditioning air for human comfort mat also be divided into two main sections – winter and summer. Frequently, the systems installed in office buildings provide control during both seasons. Complete air-conditioning provides the following services.

First, filtration of the air both in winter and summer to remove dust.

Second, calculation of the air at low velocity and with proper diffusion to prevent draughts and maintain a uniform temperature and humidity at all parts of the inhabited space.

Third, introduction of enough fresh air from the outside atmosphere.

Fourth, heating of the air in winter.

Fifth, cooling of the air in summer below the outside atmosphere.

Sixth, humidifying the air in winter to a relative humidity of at least 20-25 per cent.

Seventh, dehumidifying the air in summer to a relative humidity not exceeding 55 per cent.