Booth's Mental health

[Eva Elisabeth]

Off topic, but the "drinking did not knock him out" argument reminded me of that rulers in history used to consume a certain, increasing amount of arsenic each day to slowly get their body used to a dose that would kill people not used to it and prevent murder attempts by arsenic poisoning. I know there was one ruler who was particularly known for doing this, but cannot remember who it was. If anyone knows, please post!