The incident at Dehradun railway station in the story “The Adventures of Toto” is a significant event that showcases the intelligence and bravery of the protagonist, Toto. The incident takes place when a thief tries to steal the bag of Toto's mistress while they were waiting for their train at the station.

Thief tries to steal the bag
As the mistress of Toto was busy reading a book, a thief snatched her bag and tried to run away. However, Toto, who was sitting right beside her, noticed the thief's actions and sprang into action.

Toto's heroic actions
Toto jumped on the thief's back and started biting him. The thief tried to shake Toto off, but the tiny dog clung to him tightly. As a result, the thief was unable to run away, and the commotion attracted the attention of the other passengers and the railway police.

Toto's mistress gets her bag back
The railway police apprehended the thief, and Toto's mistress got her bag back. The passengers and the police praised Toto for his bravery, and the tiny dog became the hero of the day.

Conclusion
In conclusion, the incident at Dehradun railway station is a pivotal event in the story as it establishes Toto's character as a brave and intelligent dog. Toto's actions not only helped his mistress but also prevented the thief from committing a crime.