Transom (probably a corruption of Latin
transtrum, a thwart, in a boat; equivalents are French
traverse,
croisillon, German
Losholz) is the
architectural term given to the horizontal
lintel or beam which is framed across a
window, dividing it into stages or heights.
In early
Gothic ecclesiastical work transoms are only found in
belfry[?] unglazed windows or spire lights, where they were deemed necessary to strengthen the
mullions[?] in the absence of the
iron stay[?] bars, which in glazed windows served a similar purpose.
In domestic work, on account of the opening casements, they are more frequently found.
In the later Gothic, and more especially the Perpendicular period, the introduction of transoms became very general in windows of all kinds.
The phrase "over the transom" refers to works submitted for publication without being
solicited; the image being invoked that of a writer tossing a manuscript through the open
window over the door of the publisher's office.
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