parallel rulers

parallel rulers is a navigational instrument or ruler.

Overview

Catalogue entries for instruments state maker, signature, completeness and working condition. VALÉORINE records this subject so that lots referring to it can be described consistently.

In detail

drafting instrument used to draw parallel lines

Sources

Each source is named with the standing the house places on it, so the evidence can be weighed rather than taken on trust.

reference work · Reputable secondary · Wikipedia
“Parallel rulers”, English Wikipedia, consulted as further reading
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reference work · Reputable secondary · Wikidata
Wikidata, structured authority record Q2051620: parallel rulers
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