he had been smiling for most of the past sixteen hours , but most of it was due to a large rat that gotten caught in empty jar of peanuts that it had climbed into and that had begun to use his glass jail as a small vehicle to drive around the lot before finally dying struggling with a loose popcorn kernel that had rolled into the jar with it , and , thinking the kernel was a new prisoner , had tried to make it his bitch , only to choke on it .