You quickly understand that the quivering is only because of he stress, fright and tension you've been subjected to. The phial's contents have another purpose. You quickly realize that when suddenly your mind gets incredibly foggy and you can only feel dizziness. You have issues forming thoughts. Your eyes shut themselves forcibly and you can't seem to stop them. You feel tired, incredibly so and you can sense yourself being dragged into unconsciousness, no matter how you try to shake yourself out of the sensation. Just what is happening? It's really frightening!
Then you see Tarzan with a big smile and you understand. Chloroform! The awful ape-man has made you inhale it and now you are under its influence. Soon you'll be sleeping! But just why did Tarzan do that? You try to ask him but your voice solely produces slurred grunts. Luckily, Tarzan answers for you.
"You not ape," he says gravely, arms crossed over his chest. "You bad man from another world, transformed. Transformed like Tarzan's jungle friends, but I know you not friend. You bad man. You come in Tarzan's home but you not friend. You not proud gorilla friend. You just bad man. You not harm Tarzan home and Tarzan friend! You be punished! You bad bad intruder!"
As your vision definitely fades to black, you wonder what is the punishment Tarzan has in mind for you.