Classical order Classical order An order in architecture is a certain assemblage of parts subject to uniform established proportions, regulated by the office that each part has to perform. Coming down to the present from Ancient Greek and Ancient Roman civilization, the architectural orders are the styles of classical architecture, each distinguished by its proportions and characteristic profiles and details, and most readily recognizable by the type of column employed. The three orders of architecture—the Doric, Ionic, and Corinthian—originated in Greece. To these the Romans added, in practice if not in name, the Tuscan, which they made simpler than Doric, and the
Bodleian Library the "Old Schools Quadrangle", or the "Old Library") was built between 1613 and 1619 by adding three wings to the Proscholium and Arts End. Its tower forms the main entrance to the library, and is known as the Tower of the Five Orders. The Tower is so named because it is ornamented, in ascending order, with the columns of each of the five orders of classical architecture: Tuscan, Doric, Ionic, Corinthian and Composite. The three wings of the quadrangle have three floors: rooms on the ground and upper floors of the quadrangle (excluding Duke Humfrey’s Library, above the Divinity School)