In 2013, I started a series of geocaches to take a “deep dive” into musical works that I have perform as part of my church choir. This cache is the successor to the first in the series, which is now reworked as a new hide in a new location.
As I was pondering a name for what was the first cache, I glanced over and saw the score for a piece of music that I have been studying and which our choir presented in April 2013:
Famous Musical Work (FMW) #1
Mass in D Minor (Nelson Mass)
by Joseph Haydn
Franz Joseph Haydn was an Austrian composer in the late Classical period (about 1750 to 1820).
He was instrumental in the development of chamber music such as the string quartet and piano trio. His contributions to musical form have led him to be called "Father of the Symphony" and "Father of the String Quartet".
Haydn spent much of his career as a court musician for the wealthy Esterházy family at their Eszterháza Castle. Until the later part of his life, this isolated him from other composers and trends in music so that he was, as he put it, "forced to become original". Yet his music circulated widely, and for much of his career he was the most celebrated composer in Europe.
He was a friend and mentor of Mozart, a tutor of Beethoven, and the elder brother of composer Michael Haydn.
The Mass in D Minor is simply autographed as "Missa" ("Mass" in Latin) in the National Library at Vienna. However, it was termed by Haydn, "Missa in Angustiis" (literally "narrow," "constricted"). This may be more freely translated as "Mass in Time of Fear" or "Mass in Troubled Times." Two years earlier he had written "Mass in Time of War" when the French were invading Austria. This mass also was written in a time of war.
Haydn composed the work July 10 - August 31, 1798. At roughly the time this work was composed, Lord Admiral Nelson won an historic naval battle over the French at Abukir, August 3, 1799 News reached Vienna weeks after the mass was finished. But when Nelson and Lady Hamilton passed through Austria in September 1800, they stayed at Eisenstadt Castle as guests of Prince Esterházy, and several concerts were arranged in their honor. The "Nelson Mass" and the Te Deum seem to have been among the works performed; soon afterward the Mass became known in Austria and Southern Germany under its present title.
The "Nelson Mass" was first performed at the Bergkirche in Eisenstadt, to celebrate the Name Day of Princess Esterházy in September 1798. It was for this purpose that Haydn wrote all six of his late Masses, which stretch from 1796 to 1802. The later masses were composed after taking a short hiatus when elaborate church music was inhibited by the Josephinian reforms of the 1780s. The late sacred works of Haydn are masterworks influenced by the experience of his London symphonies and highlight the soloists and chorus while allowing the orchestra to play a prominent role.
Due to the political and financial instability of this period in European history, Haydn’s patron Nikolaus II dismissed the Feldharmonie, or wind band octet, shortly before Haydn wrote the Mass. Haydn, therefore, was left with a "dark" orchestra composed of strings, trumpets, timpani, and organ.
The Nelson Mass is scored, apart from the voices, strings and organ, only for three trumpets and kettledrums. The D minor sonority, absence of woodwinds and "the acid, biting texture of the trumpets" contribute to the asperity (roughness) of the piece. The organ part in the Nelson Mass is often written out - as opposed to Haydn's more usual method of treating the instrument as a basso continuo (partially improvised accompaniment played on a bass line). Haydn played the organ himself in the first performance. [Perhaps this is why an explicit organ score was not usually created?]
Though in 1798, when he wrote this Mass, Haydn's reputation was at its peak, his world was in turmoil. Napoleon had won four major battles with Austria in less than a year. The previous year, in early 1797, his armies had crossed the Alps and threatened Vienna itself. In May 1798, Napoleon invaded Egypt to destroy Britain's trade routes to the East.
The summer of 1798 was therefore a terrifying time for Austria. What Haydn did not know when he wrote the Mass, but what he and his audience heard (perhaps on the very day of the first performance September 15), was that on Aug. 1, Napoleon had been dealt a stunning defeat in the Battle of the Nile by British forces led by Admiral Horatio Nelson. [Perhaps] Because of this coincidence [or because of Nelson's visit to Austria in 1800], the Mass gradually acquired the nickname "Lord Nelson Mass".
Landon wrote that this mass "is arguably Haydn's greatest single composition". The work was first published in 1804 by Breitkopf of Leipzig.
Composition
The text, slightly altered, is taken from the Latin Mass of the Catholic church. It includes the following sections.
A Connection with Admiral Nelson
In September of 2012, we were visiting Sydney, Nova Scotia, Canada. St. George's Anglican Church is not generally open, but the rector was there and gave us an impromptu tour. The church, built in 1790, is a "Royal Peculiar," meaning that it is the designated church where the monarch will worship if she or he is visiting the area. The church was also the "seat" of the local bishop. An interesting, though not authenticated, feature is The Bishop's Chair. It is said that it came from the wardroom of the HMS Victory and it serves as a memento of the time Lord Nelson and his crew once attended service at St. George's.
A Connection with Joseph Haydn
In July of 2006, our church choir visited Vienna and sang for a service at St. Stephen's. Haydn worked as a professional musician there early in his career, 1740-1749. (I was introduced to geocaching by Bassmondo on that trip and spotted my first geocache in Vienna at the "Monument against War and Fascism" near the Vienna Opera House. GCR8N2 Philipphof.)
About the Cache
Please inspect the area carefully. The cache may not be missing - merely Haydn. 
Sources: H. C. Robbins Landon, 1962; Wikipedia Missa in Angustiis; Wikipedia Joseph Haydn; Cape Breton County Churches
Congratulations to Lovejoy for FTF on the redux
and to TeamOxford for FTF on the original hide!