The hands on program lasted about an hour and a half. On each table were samples of some of the ingredients — angostura bark, wormwood, calisaya, caraway — used to make bitters. We were invited to smell them. Later copies of vintage bartending manuals were passed around for us to examine. Finally we tasted — by placing a drop of the potent liquid on the side of the hand — samples of bitters dating all the way back to the 1860s.