Manuscript Am.B. 340 was presumably written by Wilhelm Karges. As was usual in those days composers were indicated with their initials rather than there full names. Or were not indicated at all. If Karges indicates no composer then we can only assume the piece was composed by Karges himself or by an anonymus master.
But even if Karges did indicate initials, it is uncertain who the composer was. In three cases Karges writes "F.S." near the title of the composition. In one case (the Fugue in d) it is a composition by Johann Jacob Froberger (FbWV 416). Does this mean the other two compositions are by Froberger as well? Strangely enough, in two other cases Karges indicates Froberger as the composer by using his full surname.
The Capricio in D is one of the three compositions where Karges wrote "F.S." below the title of the piece. It could be based on an original by Forberger, though that supposed original is unknown to me. It does not feature in my collection of printed Froberger music. As that collection is far from complete, it could well be an oversight on my part. As usual, if anyone known on which original this composition is based, I'd very much like to hear it.
Though called "Capricio" it is actually more like a fugue. In the first two pages the music is based on a single theme, that in the first bars is presented in a typical fugue exposition. At the end of the second page Karges writes a closing cadens after which the music could end. Karges however carries it forth for another page, based on another theme, even though he starts this section with the original fugue theme. In my opinion it is again an example of the practical character this manuscript has for every days usage during a service. The music could end with the cadence at the end of part two. And if the occasion needs a bit more length of music, there is an extension that follows naturally from the music before the cadence, so hardly anyone notices you play actually an extension.
The recording was done with the Hauptwerk software and the sample set of the Silbermann organ of the Stadtkirche Zöblitz by Prospectum (http://www.prospectum.com/index.php?language=english&id1=2&id2=8).