The Latin title of a very ancient hymn to
the Holy Ghost, sung in the Ordination Offices, appropriate to
Whitsun Day, and formerly sung at the celebration of the Holy
Eucharist. The authorship of this hymn is commonly ascribed to St.
Ambrose, A.D. 350. The first English version (added to the
Prayer-book in 1662) has been attributed to John Dryden.