"The Uffenbach brothers are in Utrecht, visiting Prince Franz von Darmstadt. He shows them works by his engineer and instruments. The court master "Von Rarneytsky" gave Uffenbach several letters to bring back to Darmstadt. Uffenbach says goodbye to Gemmingen and Sulznern. That evening he packs and gets ready for the travel ahead. He notes the things he has not been able to see, and makes references to his sources. This included the library and collection of Gravii, which had came in the possession of the Elector through Gravii's daughter and the Elector's antiquarian Matth. le Roy."