page_title: Perpend stone
hierarchical_section_title: Perpend stone
caption_attribution_description: English: Footpath at Nab End, Longwood Why such tall walls? The land on the right is otherwise unenclosed and has moorland vegetation, and there is a field of grass on the left. The cross-section of the wall shows how it is tapered from bottom to top.
context_page_description: A perpend stone, perpend, through stone, bond stone, or tie stone is a stone that extends through an entire wall's width, from the outer to the inner wall. Such stones are especially used to lock two wall layers structurally together. Usually stone walls are built with two layers of stone, an inner and an outer layer, with the space between them sometimes filled with rubble.
  The term perpend is also used to refer to a joint in brickwork also called a cross joint or, when extending through the entire wall, a transverse joint or perpend bond.
context_section_description: A perpend stone, perpend (parpen, parpend, perpin, and other spellings), through stone, bond stone, or tie stone is a stone that extends through an entire wall's width, from the outer to the inner wall. Such stones are especially used to lock two wall layers structurally together. Usually stone walls are built with two layers of stone, an inner and an outer layer, with the space between them sometimes filled with rubble. 
  The term perpend is also used to refer to a joint in brickwork also called a cross joint or, when extending through the entire wall, a transverse joint or perpend bond.
caption: The bond stones seen on the end of the right wall extend across the width of this tall, battered, dry-stone wall
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