Definition
An obsolete English fiscal impost levied in London on salt imported by aliens, assessed at one-twentieth (5%) of the quantity imported. The duty was collected in kind rather than in money — that is, the twentieth part of the salt itself was taken, not a cash equivalent of its value. Grainage belongs to the broader historical category of ancient customs duties and port tolls that predated the consolidation of English excise and customs law.
Common Language
Modern common usage (Wiktionary): In sericulture (silk production), grainage refers to the selection and storage of silkworm cocoons or eggs for breeding purposes.
Historical common usage (Webster's 1913): Not recorded. The term did not appear to circulate in general English usage in the nineteenth century.
Editorial note: The legal and modern common meanings share no relationship whatsoever. A researcher encountering "grainage" in a historical London customs or trade document should not import any meaning from the sericulture usage. The two senses are false cognates that happen to share a spelling.
Common Confusion
Grainage is occasionally grouped loosely with other ancient London port duties such as scavage, tronage, and pesage. These were distinct imposts with different objects and rates. Scavage was levied on goods shown for sale by foreign merchants; tronage was a weighing toll on wool; pesage covered goods sold by weight more generally. Grainage was specifically and narrowly a duty on imported salt, assessed by measure rather than weight or value. Conflating these terms in research leads to mischaracterization of the fiscal regime under which a particular merchant or transaction operated.
Why It Matters in Research
Grainage is a term researchers will encounter almost exclusively in two contexts: (1) historical documents relating to London's port trade, alien merchant activity, and municipal finance from the medieval and early modern periods, and (2) legal dictionaries and treatises that catalog obsolete imposts for completeness.
The term is dead law. No modern jurisdiction imposes grainage, and it had ceased to function as an operative legal concept well before the nineteenth century. Its presence in Black's, Bouvier's, and Rapalje & Lawrence reflects those dictionaries' function as historical archives as much as practical references — researchers using those sources should understand that grainage entries describe what once was, not what is or was in any living sense by the time those dictionaries were compiled.
For corpus researchers, the practical significance is navigational: if grainage appears in a primary source document, it anchors that document in a London commercial or customs context and likely signals involvement of alien (non-English) merchants, since the duty was specifically assessed on aliens rather than denizens. This distinction between alien and denizen merchant status carried substantial legal consequences in medieval and early modern English law, affecting not only customs rates but also rights to sue, hold property, and engage in trade. Grainage is therefore a useful marker term — its presence is diagnostic of a specific legal and commercial environment.
The Rapalje & Lawrence entry is garbled in its surviving form, running "grainage" into a reference for "grammar school" — a typographical artifact of nineteenth-century dictionary production that researchers should recognize as a corruption rather than a substantive connection.
Historical Dictionary Support
All four source dictionaries agree on the core definition without variation: an ancient London duty of one-twentieth of imported salt, levied on aliens. The consistency is unsurprising given that the term had no living legal application by the time any of these dictionaries were written; compilers were all drawing on the same historical record rather than observing contemporary practice.
Bouvier's formulation ("consisting of one-twentieth part of the salt imported into that city") most precisely captures the in-kind nature of the assessment. Black's first and second editions add the alien-merchant limitation explicitly ("imported by aliens"), which Bouvier's implies but does not state. Neither Bouvier's nor Black's provides a date of origin or abolition, and none of the four sources cites underlying statutory or charter authority for the duty — a gap that researchers tracing the duty to its origins will need to fill through primary sources outside the Law Mind dictionary corpus, such as records of the City of London or Parliamentary rolls.