HANAPER, used particularly in the English Chancery
of a wicker basket in which were kept writs and other
documents, and hence it became the name of a department
of the chancery, now abolished, under an officer known
as the clerk of the hanaper, into which were paid fees
for the sealing of charters, patents, &c., and from
which issued certain writs under the Great Seal.
From "hanaper" is derived the modern "hamper."

Encyclopedia Britannica, 1911