Unknown logbook and 300-year-old sheet music traced back to Tordenskiold’s ship

15. September 2023

Unknown logbook and 300-year-old sheet music traced back to Tordenskiold's ship

The Danish National Archives has made a remarkable discovery in connection with an extensive review of thousands of weather observations from centuries of voyages. A logbook of unknown origin with sheet music for a minuet was discovered. Now, the mystery has been solved, and the notes from the sheet music have been brought to life for the first time in more than 300 years.


An unusual find

Two archivists from the Danish National Archives embarked on major detective work to trace the origin of an unknown logbook. When they turned to the first page of “Journalbog fra den 1ste Januar indtil 8. Maj 1715, holden på et Orlogskib” [Logbook from the 1st of January to the 8th of may 1715, kept on a warship] (Thott 986 folio) at the Royal Library, they found a series of meticulously handwritten notes without dates or explanations as to why they were there, and with no information about the ship’s name.

“It’s quite an unusual find,” says archivist Adam Jon Kronegh, who is also known for solving archive mysteries on the TV series “Forsvundne arvinger” [Heir Hunters]. “We have a collaboration with the Danish Meteorological Institute, where we collect old weather observations from ship’s logs for use in future climate research. We have already gone through a lot of ship’s logs here at the Danish National Archives, and we have never found sheet music before. At the same time, we are always on the lookout for new weather data, and that is how we found the sheet music in a logbook at the Royal Danish Library.”

What was the name of the ship?

The archivists made every effort to find out, why the sheet music was there and which ship had maintained the log. There was no indication, and the front of the ship’s log was blank.

The only thing they know was that it covered the period from January 1, 1715, to May 8, 1715, and that it was allegedly an original document. It was an active period in Danish maritime history because of the Great Northern War.

Additionally, a number of precise dates of events were recorded, which captains were legally required to document. “It was customary for ships to record when they passed and saluted other ships with blank cannon fire,” explains Adam Jon Kronegh. “We could see that this ship had saluted other ships, including Nellebladet, Høyenhald, and Leoparden. We then found the logbooks of these ships and could see which ships they had noted saluting on specific dates. In this way, we hoped to mirror the information in the logbooks of those ships we knew ‘our’ ship had encountered.

Unfortunately, none of the other ships had noted in their logbooks that they had saluted ‘our ship,’ so it was a dead end.”

The key to Tordenskiold

An essential clue was still missing to solve the mystery. The archivists noticed that the ship’s log seemed to serve as a kind of draft. It had no official stamps and contained strikeouts and corrections.

In 1795, Rasmus Nyerup had only noted that the journal appeared to be original.

“Then we had an idea: What if we have the original logbook, the one that was carried on the journey and used as a draft for the formal ship’s log, which was the official document and often created only when the ship was safely in port? Maybe we could find the final ship journal in the Danish National Archives’ collection?” says archivist Joen Rommedahl. “Unfortunately, we didn’t find it in the National Archives’ collection, but we had a growing suspicion that it could be Tordenskiold’s original logbook, even though we could hardly believe it. In that case, there would also be a natural explanation for it not being in Denmark, since all of Tordenskiold’s logbooks were handed over to Norway where Tordenskiold originated from.”

This turned out to be correct. At the Norwegian University Library (NTNU), Joen Rommedahl found the digitization of Tordenskiold’s official logbooks. By comparing the text from selected dates in the ship’s log at the Royal Library with the official logbook in Norway, the archivists finally found the ship’s name and the name of the captain. The texts in Denmark and Norway were completely identical.

“The whole puzzle came together with this last crucial piece,” exclaims Adam Jon Kronegh enthusiastically. “Our best explanation for the identical texts is that the ship’s log we found in the Royal Library’s collection with no name or origin is actually Tordenskiold’s unknown logbook, which he had on his ship, Løvendals Galej. Furthermore, we were just lucky that there was an extra and rather unusual addition with the sheet music. You can’t find that in the official ship journal in Norway. Now we have also brought the history to life by playing the beautiful little melody from Løvendals Galej’s logbook, perhaps for the first time in more than 300 years.”

“It’s an exciting discovery and a fantastic piece of detective work. One would very much like to know the composer and whether the melody was played on Løvendals Galej, on deck, or in Tordenskiold’s cabin,” says Dan H. Andersen, Ph.D., author, and historian.

The Royal Danish Library also welcomes the discovery and states: “The journal comes from Otto Thott’s (1703-1785) manuscript collection, which was gifted to the Royal Danish Library after his death in 1785. In addition to unique European manuscripts from the Middle Ages and the Renaissance, Thott’s manuscript collection also contains sources for various areas of knowledge in 18th century Denmark, and it continues to yield new knowledge. We are pleased that the journal and sheet music have now been accurately identified.”

Hear the music


  • ROPEWALK (Rescuing Old data with People’s Efforts: Weather and climate Archives from LogbooK records) is a collaboration between the National Archives of Denmark and the Danish Meteorological Institute.
  • The project will provide significant historical weather data for Danish and international research.
  • It is supported by the A.P. Møller Foundation with 14.25 million DKK.
  • The project is led by Archivist Adam Jon Kronegh from the Danish National Archives, who is an expert in historical climate data, and Dr. Martin Stendel, a climate researcher from the Danish Meteorological Institute. They have developed the project together, and Martin Stendel has been working on the idea of harvesting climate-related data from older written sources for over 20 years.