Penn was now a strongly built young man of eighteen, with large eyes and long dark hair falling in curls about his shoulders. For a brief time he gave himself up to the fashionable social life of Paris. Later he engaged in study at school for something like a year, and then spent another year in travelling through France and Italy. When he returned to England after two years' absence, he was a cultivated young gentleman, very different from the sober youth who on leaving Oxford had been called by his companions "a Quaker or some other melancholy thing." [Illustration: WILLIAM PENN'S FAMOUS TREATY WITH THE INDIANS.] The following year, however, Penn's gay spirits were disturbed by the awful plague that fell upon London. The Admiral, noting the serious look and manner of his son, again sent him from home--this time to Ireland--for diversion. While Penn was in Ireland an insurrection broke out, and he volunteered as a soldier. Military life evidently appealed to him, for he caused a portrait of himself to be painted, in full armor. While still serving as a soldier, Penn learned that the Quaker, Thomas Loe, was preaching near by, and went to hear him once more. The Quaker ideas now took complete possession of him, and he embraced the new religion with his whole heart. A little later, when he was arrested in a Quaker meeting-house and thrown into prison, his father was indignant because William had brought upon his family such humiliating disgrace. After William's release from prison, however, the stern old Admiral in his great love for his son said he would forgive his peculiar customs if only he would remove his hat to his father, to the King, or to the Duke of York. But on praying over the matter, Penn said he could not do it. One day, on meeting the King, he had the boldness to stand with his hat on in the royal presence. Instead of getting angry, the fun-loving King Charles laughed and took off his own hat. "Why dost thou remove thy hat, friend Charles?" said William Penn. "Because," answered the King, "wherever I am it is customary for one to remain uncovered." But the Admiral's patience was by this time exhausted. He drove his wilful son from his presence, and told him to begone for all time. Fortunately for William, his mother begged for him, and so did others who recognized the earnest and sincere purpose of the young Quaker. His father therefore forgave him once more, and allowed him to return home. [Illustration: The Pennsylvania Settlement.] From this time on William Penn used his influence--which was by no means small--in behalf of the persecuted Quakers; but he had to suffer the consequences of his own fearlessness. Many times was he thrown into prison, there to remain, it might be, for months. Yet even in prison he spent his time in writing books and pamphlets, explaining and defending the Quaker religion. Indeed, his labors were unceasing, so firm was his faith in Quaker ideas.