From "A History of the Organs at Emmanuel UCC" by Shawn Gingrich, 1994:
At the evening service on Sunday, July 31, 1887, this pipe organ was used for the last time. The following paper, prepared by Elder Henry Wirt, was read:
The history of the purchase and cost of our old organ, those who were mainly instrumental in getting it; who contributed to its cost, and what the cost was, are facts that have been entirely lost. There is no record anywhere on the old church books relating to any of these things. Tradition says that its cost was $400; but this seems such a low price for an organ of this size, that it can hardly be relied upon as being correct.

The only record that can be found relating to the organ is an advertisement in the German Hanover Gazette of August 31, 1805, of which the following is a translation:
"Notice. -The German Reformed congregation of Hanover and vicinity are hereby notified that the new organ for the church, which has been built by Mr. Bachman of Lititz, Pa., is now so far completed that it can be sent for. Messrs. Ludwig Schwartz and Michael Nyman have volunteered to send their teams to Lititz for the purpose of bringing the organ to this place, and will start for that purpose next Monday. As soon as it has been put up and ready to be used, public notice of the same will be given."
Peter Winebrenner, John Philip Starck
Deacons of the Congregation

There exists a subscription list for the purpose of remodeling and repairing the organ. It is possibly from January 1859 when the consistory requested that Mr. Henry Wirt play the organ for services. At this time they ordered that, if necessary, the organ be repaired at the expense of the congregation. On the back of one of the subscription sheets someone jotted down the layout of the stop knobs. Here follows the listing as it appears:
Left Right
1 . Principal Open Diapason

1. Twelfth Quinta Dehn
2. Mixture Fifteenth
3. Open Flute Stop=

The organ was dismantled on Monday, August 1, 1887. The following is an article which was published in the September 10, 1887 issue of the Hanover Herald:
"The old organ removed from Emmanuel's Reformed Church was taken to Marietta, this week, the removal being made by Messrs. Mamby & Son, of Lancaster. The organ will be erected in a Reformed Church of which Rev. S. F. Laury, formerly of Jefferson, has recently been elected pastor. Thus, after the lapse of many years, this old instrument goes back to the county in which it was built."

The fate of the organ after its donation to the Marietta Mission Church is not definite but a few pipes and other parts, which were said to be very likely Tannenberg's work, were found in the attic of a Marietta home. This leads us to believe that the organ was disassembled and used for parts at the end of its service.

Updated through online information from T. Daniel Hancock. -- On the website, "David Tannenberg, Organbuilder," Philip T.D. Cooper writes "This organ was supposedly begun by Tannenberg and finished by Bachmann although how much of it was actually constructed by Tannenberg is not known. The organ had one manual with eight stops - six of metal and two of wood. It was probably very similar to the 1802 organ in Madison, Virginia. In 1887, it was given to the mission church in Marietta where it was used into the 20th century and then discarded."

Reportedly begun by David Tannenberg before his death. 2 wood stops and 6 of metal. Given to mission church in Marietta, PA in 1887. Used into 20th century then discarded.