I was at an event a few days ago, where a bartender mixed a drink in which he used "Jerry Thomas' own recipe bitters." I've dug up the recipe, and I invite the more adventurous among you to give this tincture a try. Thomas suggests serving his bitters as a sort of infused rum; if you'd like to use this recipe in mixed drinks, I would recommend infusing a higher proof alcohol like Everclear. For more on the logistics of preparing bitters, refer to this excellent article.
"Jerry Thomas'" own Decanter Bitters
From How To Mix Drinks, by Jerry Thomas (1862)
1 Ib of raisins
2 ounces of cinnamon
1 ounce snake root*
1 lemon and 1 orange cut in slices
1 ounce of cloves
1 ounce allspice
Fill decanter with Santa Cruz rum. Bottle and serve out in pony glasses. As fast as the bitters is used fill up again with rum.
*The one problem with the recipe is that snakeroot is highly poisonous; in the 19th century, cows who grazed in wooded areas would eat this toxic plant, and their milk would in turn become toxic. The farmers and their families who drank it came down with "milk sickness," and were stricken with vomiting and diarrhea. The affliction claimed thousands of lives, most notable Abraham Lincoln's mother. However, I suspect the death rate was not so much result of the poisoning itself, but because the medical world was yet unaware of the importance of replacing a lost fluids. It was not uncommon for sickly babies to poop themselves to death.
Perhaps snakeroot is safer in smaller concentrations, I don't know. But please, for the sake of my conscience, don't mess around with it.
On another note, below is a video I did a few years ago at Death & Company, an East Village bar that looks to pre-prohibition era cocktails to inspire modern concoctions (their menu). They're also going to be a stop on my upcoming 19th Century Pub Crawl.