There is an issue with your point, the reason for Alice's Adventures in Wonderland was to protest royalty. It was disguised as a child's book to get his point across. You complain about drug use... that's what they did then. It's completely natural to the time period that the book was written in. The bottle holds a drug that can make you feel high or low. It's also set in 1865, the world of mind is starting to be chipped away and people are seeing this dark psychotic world.