FLUTE-Antique-JGL Hartmann-Hamburg-1835?Instrument!Wood
There’s the “stethoscope” trill key - why drill a big hole when you can drill two small holes? Then there’s the foot - seems to go down to B, I think the C# key is broken - but what actuates it?
You got that right, very strange! Looks like some of the keys were added later, the ones that are stacked. I have seen the double key cups before, somewhere? It just looks like a bad idea, who’s time came and went!
Hmmm, I’ve seen that stacked system before and it was quite clever. Unfortunately, I am not so clever and can’t quite remember what was so clever about it. I think it was something to do with minimising the pressure required to close two keys by having the springs in series rather than parallel. It wouldn’t surprise me if Rick Wilson has something on it on his pages, but they report as being unavailable at the moment.
The stethoscope trill key is certainly unusual. Only thing I can think of is that the maker wanted to minimise the longitudinal length of the hole, perhaps to avoid it stifling response on a very high note. But that’s just speculation.
Terry
Hmm…
It’s a very strange flute!
I wonder how are the keys for
Stethoscope? Or speculum?
I won the other flute that he was offering, it is a early French flute made by THIBOUVILLE Pere & Fils Paris, with those classy creasent key plates, should be a fun restoration. As Glinjack would say “firewood!” 
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