So you've decided to get a flute to play Irish music. There were some wonderful flutes made in the early 19th Century. There were also some truly awful ones. And, of course, a good flute can have been damaged beyond reasonable repair.
Age is no guarantee of quality, value or usefulness.
These flutes were beautifully designed and made, and usually bear the name and address of the maker, often on every joint. Keys are often solid silver and are usually deliciously formed. Rings are usually silver, sometimes very simple, sometimes beautifully engraved. Another group of London makers from around the same period, including Potter, Monzani, and Goulding Wood, made flutes which are nice but not so useful. They tend to have small holes and consequently a small tone, rather more reminiscent of their predecessor, the baroque flute.