Terry and Steve's house (if you don't know go look at my other questions)

You know what i love about this sight when ask a dumb question it is immediately answered but when i ask a real question it takes hours to get answered

Why do artist use texture? (site 1) !

In russian churches the number of domes usually matches the number of altars. but this church has only one altar dome, and 21 symbolic ones. what normal construction device does this church lack?