This flute was made by Heinrich Eduard Baack, in New York, sometime between 1837 and 1872. All sections are marked (faintly) "E. Baack, N. York". The flute is made from lovely figured cocuswood and has nickel silver rings and a single key (Eb). It has small tone holes, typical of antique American flutes of that period, but it has a strong voice.
It has an unlined head and no tuning slide, but the head joint can be extended a few mm to adjust tuning. The flute plays in tune with itself with a bit of player input, and close to A=440 hz, with head joint extended 6-7 mm.