It's a futristic robot with programmed features and it sniffs out books. It attacks montag and doesn't like him.
Montag initially thinks he sees a person on the railroad tracks, but it turns out to be a mechanical hound.
After the Mechanical Hound stabs Montag in the leg with a needle containing anesthetic he destroys the Hound with the flamethrower he used to burn down his house.
A Mechanical Hound comes sniffing around the door as Montag is reading. The Mechanical Hound is a robotic beast programmed to track down and eliminate those who break the law.
Montag mistakes a deer for the Hound in Ray Bradbury's "Fahrenheit 451." The deer startles Montag with its sudden appearance, causing him to compare its eyes and movement to those of the mechanical Hound.
After the men leave, Montag hears the Mechanical Hound growling and lurking in the darkness outside his home. This indicates that the Hound is still a threat to him.
The Mechanical Hound smells like perfume to Montag. This unexpected smell alerts Montag to the fact that the Hound has been tampered with by Captain Beatty to track and catch him.
Montag is reading poetry just before the mechanical hound arrives. The hound's arrival should indicate to Montag that he is in trouble and that the authorities are aware of his subversive activities. His reaction is one of fear and paranoia as he realizes the seriousness of the situation he is in.
He thought that he was being watched by the robot hound from the fire house.
Because, the mechanical hound attacked it.
Because he was trapped and the mechanical hound was in the area
In the first section of the book(The Hearth and the Salamander), Montag notices the mechanical house acting very hostile toward him. Montag fears the mechanical beast. As the story progresses, the hound grows more and more hostile toward him. This is strange because it is almost like Beatty(Montag's Fire Chief) programmed the hound to react that way toward Montag, as if he knew he was hoarding the books illegally.
In Fahrenheit 451, the mechanical hound is ultimately destroyed by Montag, who uses a flamethrower to disable and destroy the robot.