He was a strange scarecrow standing there in the sun with half his old face peeled off, and half another face glaring and grinning from underneath.
"Will you drive me mad ?" he cried.

"The train--" "You shall not go by the train," said Syme firmly, and grasped his sword.
The wild figure turned towards Syme, and seemed to be gathering itself for a sublime effort before speaking.
"You great fat, blasted, blear-eyed, blundering, thundering, brainless, Godforsaken, doddering, damned fool!" he said without taking breath.
"You great silly, pink-faced, towheaded turnip! You--" "You shall not go by this train," repeated Syme.
"And why the infernal blazes," roared the other, "should I want to go by the train ?" "We know all," said the Professor sternly.

"You are going to Paris to throw a bomb!" "Going to Jericho to throw a Jabberwock!" cried the other, tearing his hair, which came off easily.
"Have you all got softening of the brain, that you don't realise what I am?
Did you really think I wanted to catch that train?
Twenty Paris trains might go by for me.

Damn Paris trains!" "Then what did you care about ?" began the Professor.
"What did I care about?
I didn't care about catching the train; I cared about whether the train caught me, and now, by God! it has caught me." "I regret to inform you," said Syme with restraint, "that your remarks convey no impression to my mind.

Perhaps if you were to remove the remains of your original forehead and some portion of what was once your chin, your meaning would become clearer.