light due

From light (noun) +‎ due (noun).

• enPR: lītʹdo͞o

light due (plural light dues)

1. A duty or toll levied on ships navigating certain waters, for the maintenance of lighthouses; light money.

• William Dwight Whitney and Benjamin E[li] Smith, editors (1914), “light-dues”, in The Century Dictionary: An Encyclopedic Lexicon of the English Language, revised edition, volumes III (Hoop–O), New York, N.Y.: The Century Co., →OCLC, page 3447.