Two vast undertakings make the name of Philip Augustus memorable in Paris--the beginning of the paving of the city and the building of its girdle of walls and towers. One day as the king stood at the window of his palace, where he was wont to distract himself from the cares of state by watching the Seine flow by, some carts rattled along the muddy road beneath the window and stirred so foul and overpowering an odour that the king almost fell sick. Next day the provost and the sheriffs and chief citizens were summoned before him and ordered to set about paving the city with stone. The work was not however completed until the reign of Charles V., a century and a half later. It was done well and lasted till the sixteenth century, when it was replaced by the miserable cobbles, known as the pavement of the League. Whether the city grew much sweeter is doubtful; certainly Paris in the sixteenth, seventeenth and eighteenth centuries was as evil-smelling as ever. Montaigne, in the second half of the sixteenth century, complains that the acrid smell of the mud of Paris weakened the affection he bore to that fair city, and Howell writes in 1620, "the city is always dirty, and by perpetual motion the mud is beaten into a thick, black and unctuous oil that sticks so that no art can wash it off, and besides the indelible stain it leaves, gives so strong a scent that it may be smelt many miles off, if the wind be in one's face as one comes from the fresh air of the country." Horace Walpole in the eighteenth century, called Paris "the beastliest town in the universe." [Illustration: WALL OF PHILIPPE AUGUSTE, COUR DE ROUEN.]