Prince Andrew wished to leave at once, but Princess Mary persuaded him to stay another day.
After a period of retirement at Fonte Avellana, he proceeded in 1069 as papal legate to Germany, and persuaded the emperor Henry IV.
Again, the arrangement followed in the Pterylographie was of course based on pterylographical considerations, and we have its author's own word for it that he was persuaded that the limitation of natural groups could only be attained by the most assiduous research into the species of which they are composed from every point of view.
But in the spring of that year, he received a letter from his mother, written without his father's knowledge, and that letter persuaded him to return.
Boris shrugged his shoulders, his Serene Highness would not have it, or someone persuaded him.