The practice of having two, three, five, seven, nine and thirteen cupolas or spires is as early as the Eleventh Century. The numbers were figurative; two signifying the two natures of Jesus Christ, three, a symbol of the Trinity, five, our Lord and the four evangelists or the five wounds, seven, the seven sacraments, the seven gifts of the Holy Spirit, or the seven recumenical councils, nine, the nine celestial hierarchies, and thirteen, our Lord and the twelve apostles. Within the dimensions are small and the light obscure. Still, the simple, nearly square disposition of the building, the enormous plain-shafted pillars which support the domes, the mass of gilding, the multitude of lamps, produce an undoubtedly grand effect. It is strikingly oriental; and as in Russian churches there are no seats, but the people stand in a mingled throng, now and then prostrating themselves and beating their foreheads on the ground, each as his own devotion may dictate, the resemblance is still more marked. All the interior is covered with fresco pictures; even the pillars have gigantic figures of the saints and doctors of the church painted upon them. From the high roof hang immense brass chandeliers of a peculiar form with many branches, capable of holding hundreds of candles. In the dim distance, seemingly a wall of gold, is the iconostas, the solid screen which in every church divides the sanctuary from the rest of the sacred edifice. The iconostas is in all cases decorated with a large number of holy pictures or icons, arranged in formal rows one above the other. It is a solid erection from side to side, from floor to roof, and in the centre are the _royal doors_, through which none may pass but the consecrating priest, or the emperor: and the last once only, at the time of his coronation. At no time is any woman permitted to enter the sanctuary. The iconostas contains sometimes as many as seven rows of images: that of the _Uspenski Sobor_[1] has five. Their arrangement is guided by certain rules and restrictions. Our Lord and the blessed Virgin must be represented on each side of the royal doors, and on the doors themselves the Annunciation and the four evangelists. On the side doors angels must be represented. Above must be the usual symbol of the Trinity figured by Abraham entertaining the three angels. [Footnote 1: Cathedral of the Assumption, Moscow.] The whole of the space behind the screen is known as the altar. The altar itself is square, or rather a double cube. Above it four small columns with a canopy form a baldachino; and the cross is laid flat upon it. Here also is placed the tabernacle or _zion_ which is often an architectural structure in pure gold with figures. There are five zions of this kind in the cathedrals of St. Sophia at Novgorod and at the Troitsa monastery. In the apse behind the altar and facing it is the _thronos_, the seat of the archbishop, with seats for priests on either side.