Rebecca Hartman's Herbwifery Forum has a monthly "blog party" on various subjects. This month the topic is "bitters".
You can find the articles posted by going to Kiva Rose's website http://bearmedicineherbals.com/?p=460
There is a superb article by Susan Belsinger on the history of commercial bitters including angosturer bitters. She also provides some interesting recipes using angosturer bitters.
Sarah,thank you for this most interesting reading matter.
I also found the history of Angostura bitters most interesting and went on to read the history section of their corporate website www.angosturabitters.com/hist.htm.There is mention ofAngostura bitters as an ingredient in "pink gin" and I have to confess I had not hears of this drink for many decades so I looked it up on Wikipedia and it is positively herbal.
The ingredients are Gin[juniper] Tonic water[cinchona/quinine] and Angostura bitters[gentian].
Apparently the bitters were added to the mix to tone down the quinine taste of the tonic water.