The Four Books of Architecture

Book, Module A standard unit of measurement derived from the diameter of the column. It ensures all parts of a building remain in proportion to one another., Architecture, Elevation A technical drawing showing the vertical front or side of a structure without perspective., Arch, Pier A solid, upright support for a structure such as an arch or a roof.

A detailed architectural woodcut illustrates the proportions and measurements of a classical archway. The diagram shows a front elevation of a semi-circular arch supported by rectangular piers with attached columns. All these elements rest on high pedestals. The drawing includes numerous measurements using the Module (MO) as the base unit. At the top, within the decorative frieze area, the label MO 4 is shown. The keystone at the very center of the arch is also marked with 4 modules. The clear height of the inner arch opening is labeled as 40 modules. Horizontal width measurements include 6 modules, 7 modules, and 2.5 modules. The side piers are divided into vertical segments, with one section marked 7 modules and another marked 26 modules and 1 part. Each pedestal at the base is labeled as 1 module. At the bottom of the image, a horizontal cross-section or plan view shows the semi-circular profiles of the column bases.