The museum suggests this instrument is from the early 18th century - and so it could be a predecessor of the 'guittar' which emerged in Britain in the 1750s. On the other hand it could be a later folk instrument. There is a more familiar looking 'guittar' next to the German instrument.
The German instrument's body size is only slightly larger than the 'guittar' next to it - but the neck is a lot longer. The guittar has (if I remember correctly) the usual twelve frets, the German instrument has more.
The rose, if it is original, looks quite crude as do the seven-holed decorations to the left and right of the bridge. But the fingerboard looks nicely finished at the end above the rose.
It's a deep-bodied instrument and so, I assume, to be played with the fingers rather than with a plectrum. The neck-body joint has the 'wings', (the black bits) found on earlier citterns but absent on guittars. The neck-body joint itself looks very chunky and very severe. But the sides are made of a familiar-looking wood - and perhaps not the wood of a folk instrument?
The pegbox has a graceful curve but it seems unnecessarily robust. There's a whole chunk of wood between the nut (made of wire) and the first peg and there are also two things here that look like frets but can't be. It's easy to see the capo and the capo holes. It's impossible to tell the stringing arrangement (such as whether it's 4x2 + extra single basses).
'Nach einem im 19. Jahr- hundert wohl im Kt. St. Gallen angefertigen, 1000 mm langen Instrument'
This instrument,a Toggenburger Halszither, looks very like the Edinburgh one: the circular finial, the number of pegs, the clunky neck-body joint, the long gap between the nut and the first peg, and the triple 'roses'.
Here is another Toggenburger Halszither:
'Toggenburger Halszither spielendes Madchen um 1820'
Again, it's a very similar looking instrument to the German instrument in Edinburgh. Toggenburger Halszithern are known from the nineteenth century, not the eighteenth.