Its external characteristics Ionic columns support a well-proportioned entablature and are employed for the building's five porticoes, the main one capped by a pediment. The columns are made of white Vermont marble with black bas-relief decorations on the shaft and capital. The word "Ion" comes from the Greek word eikon, which means image. This refers to the fact that the capitals represent images of gods. In classical architecture, the Ionic order was usually used for public buildings such as temples or theaters and included two variations: the simple Ionic order and the more complex hybrid Ionic order. Both orders feature alternating bands of volutes and unfluted columns. The White House columns are all variants of the Ionic order. The White House was originally built by Thomas Jefferson in 1814-1815. He hired French architect Benjamin Henry Latrobe to design the house. When Jefferson became president, he ordered the construction of additional rooms on the second floor that Latrobe had not completed. These additions are in a simplified version of the Ionic order called "Doric" after the traditional American building method then used in Virginia where Latrobe had trained. The Doric order has only straight lines and no curved elements like the Ionic order.