When Richard I went on Crusade, he left the Tower in charge of his Chancellor, Longchamp, Bishop of Ely. John, on usurping the kingdom, besieged the Tower, which Longchamp abandoned to him, and he committed it to the care of the Archbishop of Rouen, who held it till Richard’s return. When John’s kingdom was invaded by the French Dauphin, Louis, at the invitation of the rebellious barons, the Tower was handed over to him, but he does not seem to have resided there. The next important builder after William the Conqueror was Henry III. A good deal of English fortification work is to be attributed to him. His master mason at the Tower was Adam of Lambourne, but the King himself may be called his own clerk of the works. He built the outer wall facing the ditch which had been dug in Norman days, and of course supplied with water from the Thames. It will be remembered that this King was the builder of the greater portion of Westminster Abbey; whatever his defects as a ruler, he was a man of learning and taste, and he decorated the Norman chapel in the White Tower with beautiful frescoes and stained glass, and gave bells to St. Peter’s Church on Tower Green. The Lantern Tower, on the new wall, he chose for his bedroom, and built a tiny chapel in it for his own devotions, which was so used by his successors until the tragedy of a king murdered before the altar destroyed the sanctity. Traitors’ Gate, also, was his work, the great entrance from the river side, and a very noble piece of engineering; how it got its name we shall see abundantly hereafter. A yet more important work of his, and for a while most unpopular, was the Wharf: the strip of bank alongside the river like the Thames Embankment of our own day. Adam of Lambourne was the engineer also of this remarkable work. Piles of timber were driven into the mud, and rubble thrown in between them, and then the whole mass was faced with a barrier of stone. At the beginning of the work the high tide washed it down, and carried away completely a tower which he was constructing to guard it. The citizens sent a remonstrance, not only against the expense, but against the harm which they considered it would cause to trade navigation, but the King persisted and ordered Adam to make his foundations stronger. A cry was even got up that the ghost of St. Thomas of Canterbury had appeared to denounce the work. But the King’s wisdom was so far justified by the result, that there to-day is the Wharf, and its foundations are firm as ever.