On June 22, 1918, four people were arrested and over one hundred waiters taken into custody over the apparent widespread practice of poisoning by waiters in Chicago. Guests who tipped poorly were given “Mickey Finn powder” in their food or drinks.[10][11][12][13][14][15][16] Chemical analysis showed that it contained antimony potassium tartrate,[12] well known emetic drug that besides vomiting can cause headaches, dizziness, depression and can be lethal in large quantities. W. Stuart Wood and his wife were arrested for manufacturing the powder, and two bartenders were arrested for selling the powder at the bar at the waiters’ union headquarters. Wood sold packets of the powder for 20 cents[17] and referred to it as “Mickey Finn Powder” in a letter to union bartender John Millian.[18] A follow-up article mentions the pursuit of a man named Jean Crones who was believed to be responsible for poisoning over 100 people at a Chicago University Club banquet at which three people died.[19][20]