Glossary · A
Ad triangulum
Design by the equilateral triangle: heights set at √3⁄2 of the width or its divisions, as proposed for Milan Cathedral in 1391.
See also: Ad quadratum
Rules that use the word
Ad triangulum: the equilateral triangle. Alternatively, fit the section to an equilateral triangle standing on the width, so that the height is √3⁄2 of the width, and take the levels at equal divisions of that height.
The √3 rectangle and the equilateral triangle. Swing the diagonal of a √2 rectangle to obtain a rectangle of 1 : √3, the proportion of an equilateral triangle’s height to half its base, used for setting out by triangles (ad triangulum).
Where it appears in the book
In the chapters Proportion and Number, Romanesque and Gothic.
Nearby in the glossary
Abutment · Acanthus · Acroterion · Ad quadratum · Adhishthana · Aedicule · Agora · Aisle