Definition
Perga is an archaic unit of linear land measurement equal to sixteen and one-half feet. The term appears in historical legal documents as a variant spelling of "perch," a unit used in surveying and the description of land boundaries. It carries no independent legal meaning beyond its function as a measure of distance, and its relevance today is confined to the interpretation of older deeds, grants, and conveyances in which land dimensions were recorded using pre-metric or pre-standardized survey terminology.
Why It Matters in Research
Researchers encountering perga in historical land records, colonial grants, or early common law conveyancing documents should treat it as synonymous with perch and read it as sixteen and one-half feet. The term is a spelling variant only — it signals no distinct legal doctrine or measurement system. The primary research trap is misreading the abbreviation or unfamiliar spelling and treating the dimension as uncertain when in fact it is fixed. Because early deed language was not standardized, a single instrument might use perch, perga, pole, or rod interchangeably, all referring to the same linear measure. Researchers working with chain-and-link survey descriptions should also note that forty perches equal one furlong and 320 perches equal one mile under the traditional English land measurement system, which may be relevant when reconstructing the boundaries of historical parcels. Black's 2nd edition directs readers from perga to the main entry for perch, confirming that perga is a cross-reference term rather than a substantive legal concept.
Historical Dictionary Support
Black's Law Dictionary (2nd Ed.) Supplemental defines perga simply as "a perch of land; sixteen and one-half feet" and directs the reader to the perch entry. No other historical legal dictionary surveyed treats perga as a distinct term with independent legal significance. The term does not appear in standard modern editions of Black's, reflecting its obsolescence as active legal vocabulary. Its survival in the supplemental material of older editions is consistent with the broader pattern in which 19th-century American legal dictionaries preserved archaic land measurement terminology still found in documents originating under English common law and early colonial land administration.
Jurisdictional Note
The term is not jurisdiction-specific but appears most commonly in land records from jurisdictions with English common law roots where metes-and-bounds surveying was the historical practice, including much of the eastern United States and former British colonial territories.