What did Montag learn from Granger in Fahrenheit 451?
Granger teaches Montag how to evade the pursuit of the mechanical hound and others, and how to memorize books.
Granger is “the man who seemed to be the leader of the small group.” He gives Montag a drink that will “change the chemical index of your perspiration” so that he will smell like two other people and the mechanical hound won’t find him.
Granger explains that Montag lost his followers at the river, but they have to catch someone so they will find a scapegoat.
The show's got to have a snap ending, quick! If they started searching the whole damn river it might take all night. So they're sniffing for a scape-goat to end things with a bang. Watch. They'll catch Montag in the next five minutes! " (part 3)
The mechanical hound takes the man, and his face is never known in focus so even his friends and family would never know.
Granger introduces him to the various men in the secret book society. They have perfected their memory so that they can remember anything they read once. Each one is a different book. They teach Montag, and he has a sense of purpose.