Anchor plate

Anchor plates are used on exterior walls of masonry buildings, for structural reinforcement against lateral bowing.

"[1] Although there are many types of anchors or anchorages, according to the Dictionary of Architecture and Construction, an anchor plate specifically is a "wrought-iron clamp, of Flemish origin, on the exterior side of a brick building wall that is connected to the opposite wall by a steel tie-rod to prevent the two walls from spreading apart; these clamps were often in the shape of numerals indicating the year of construction, or letters representing the owner's initials, or were simply fanciful designs.

[5] In Roman technology, wooden tie-beams (or tie rods) were used between arches to negate the outward horizontal forces between them.

[6] Iron tie rods would later be used as a device to reinforce arches, vaults, and cupolas constructed across Medieval Europe.

[7][8] In the modern era, tie-rods are made of iron or steel, and serve to reinforce vaults, arches, and in general masonry structures.