Angostura bitters are an old condiment, the one traditionally used to make "pink gins".
This involved taking the cocktail glass and adding just a couple of drops of bitters to it, then swirling it around to cover the inside of the glass, before adding the gin.
They were quite "posh" drinks, so if there is a way of getting this thing to work for dispensing a very small amount, I can see how something attractive and with work done on it, (the colour and the cutting) would have been used.
Angostura bitters used to come in a glass bottle, completely covered in (torn and age-spotted) cream coloured paper, (with dark drips of suspicious looking-stuff down it) with a nozzle part at the top that is just like the tops you still get on bottles of L&P.
These bottles of bitters lasted a very long time. I'm not absolutely sure they're still even legal.
My Grandpa had some in his drinks cabinet.