Box-days.

Chambers's Encyclopaedia, Volume 2: Beaugency to Cataract, p. 375

Box-days. These are days appointed by the Court of Session in Scotland, in the vacations and Christmas recess, on which pleadings or other law-papers may be lodged or filed, the object being to expedite the procedure, notwithstanding the vacation or recess. The name is derived from the fact that all printed papers in the Court of Session must be placed in boxes, one for each judge, for each legal society, and for the reporters. These boxes were introduced in 1690 to avoid the evil of private solicitation of judges.

Source scan(s): p. 0386