The main Greekinfluence on Roman art was in sculpture. During the period of theRoman Republic, Roman sculpture was portraiture sculpture (busts).The establishment of rule by emperors saw the introduction of fullbody statues in the Hellenistic style of the Greeks. Due to theperfection of Greek sculpture the Romans did not try to imitatetheir sculpture. They either hired Greek sculptors or madereproductions of statues by great Greek sculptors.The Romans adopted thethree Greek orders (styles) for making columns: Doric Ionic andCorinthian. They also introduced the Composite order, which mixedelements of two of the mentioned orders. They used columns to buildporticoes and temples. Most of the latter were built in the Greekstyle. Some of the later temples, instead, were circular and had adome and were a Roman invention. For the rest, Roman architecturewas Roman. The Romans effected what historians have called theRoman architectural revolution which transformed ancientarchitecture by making large scale use of concrete, the arch andthe vaulted arch (or vault).The Romanslearnt mosaic making form the Greeks and most recorded names ofRoman mosaic workers are Greek. Sometimes Roman mosaics andfrescoes depicted scenes from Greek myths.