Trail:

Glossary

Potence
(Scots): Rotating ladder for access to nesting boxes in a doocot (dovecote).
Pound lock
(canals): A chamber with gates at each end allowing boats to float from one level to another. Successor to the flash lock.
Pre-cast
Of concrete: cast as components before construction.
Pre-stressed
Of concrete: incorporating tensioned steel rods.
Predella
In an altarpiece, the horizontal strip below the main representation, often used for subsidiary representations.
Prefabrication
Manufacture of buildings or components off-site for assembly on-site.
Presbytery
The part of a church lying east of the choir where the main altar is placed. Also a priest’s residence.
Principals
In a roof, a pair of inclined lateral timbers or rafters of a truss. Usually they support horizontal side timbers called purlins, and mark the main bay divisions.
Pronaos
The space within the portico of a classical temple.
Prostyle
Of a porch or portico: with columns standing free.