Entablature being called petrification. The structure of the entablature varies with the three classical orders: Doric, Ionic, and Corinthian. In each, the proportions of the subdivisions (architrave, frieze, cornice) are defined by the proportions of the column in the order. In Roman and Renaissance interpretations, it is usually approximately a quarter of the height of the column. Variants of entablature that do not fit these models are usually derived from them. Pure classical Doric entablature is simple. The architrave, the lowest band, is split, from bottom to top, into the guttae, the regulae, and the taenia. The frieze is dominated by
Giacomo Barozzi da Vignola company with Baldassare Peruzzi, Giulio Romano, Andrea Palladio and others furnished material for an exhibition in 2001 His two published books helped formulate the canon of classical architectural style. The earliest, "Regola delli cinque ordini d'architettura" ["Canon of the five orders of architecture"] (first published in 1562, probably in Rome), presented Vignola's practical system for constructing columns in the five classical orders (Tuscan, Doric, Ionic, Corinthian and Composite) utilising proportions which Vignola derived from his own measurements of classical Roman monuments. The clarity and ease of use of Vignola's treatise caused it to become in succeeding centuries the most published