This section of the book is from the "Stories of Animal Sagacity" book, by William Henry Giles Kingston.
Mrs F—’s father-in-law had a donkey named Bob, which was kept in a field with other animals, and grazed quietly with them, but jealously guarded the entrance against all intruders. If any strange cows, sheep, or pigs ventured within his territory, Bob instantly ran at them full tilt, and hunted them from the premises, kicking out his heels and biting whenever he had the opportunity. Indeed, if he but saw them inclined to come in, he would stand in the gap and defend it bravely. His vigilance was so great that it was considered unnecessary to have a herdsman in the place.
Bob was clearly convinced that it was his duty to keep that field against all intruders. Dear young reader, when you have the property of another person to watch over, guard it as effectually as did honest Bob his master’s paddock.