It's time to get this Dubonnet on the Rocks thing cleared up. Thanks to our Hope Mountain Blues bass player, Neil, I have an answer for you.
He said he used to drink Dubonnet with Heimingway at a little cafe in Paris before the war. I can picture him doing that. He and Ernest could have had quite a discussion.
I did some more research on wikipedia and this is what I found out:
Dubonnet is a sweet, wine-based aperitif. It is a blend of fortified wine, herbs, and spices (including a small amount of quinine), with fermentation being stopped by the addition of alcohol.
Dubonnet was first sold in 1846 by Joseph Dubonnet, in response to a competition run by the French Government to find a way of persuading French Foreign Legionnaires in North Africa to drink quinine. Quinine combats malaria but is very bitter.
Ew! I can't say that I care much for sweet wine. I think we should stick with Maker's Mark, Neil.