Two of the old gates have been demolished--the Porte de Limbert in 1896, and the Porte de l'Oulle in 1900--the former, many times repaired, was the only existing example of the external aspect of a medieval gate, the latter had been rebuilt in 1786 in the Doric style. A new gate, the Porte Pétrarque, now the Porte de la République, was erected by Viollet-le-Duc when the walls were pierced for the new street; the Porte St. Dominique is also new. These noble mural defenses, three miles in circuit, twice narrowly escaped demolition--at the construction of the railway, when they were saved by a vigorous protest of Prosper Mérimée, and in 1902, when, on the pretext that they blocked the development of the city, the municipality decided to demolish the unrestored portions. Luckily the intervention of a public-spirited Prefect of Vaucluse proved successful, and they were again rescued from the housewrecker's pick. No visitor to Avignon should omit to walk or drive round the famous ramparts. Their stones have been subjected to careful scrutiny by antiquarians and the masons' marks (tacherons)--about 4,500--carefully examined and reduced to about four hundred and fifty types. Opinions differ as to the meaning of these curious signs, but there is little doubt that M. Maire's suggestion is the correct one--the workmen were paid by the piece, and each had his own private mark which he cut on the stones he laid and thus enabled the foreman to check his work. We begin at the Porte du Rhône, and skirt the older part of the walls on the northwest with their different style of corbels and machicoulis. M. Maire has no hesitation in assigning this portion to the time of Clement VI., by reason of the coarser nature of the masons' marks. Turning southwards, we pass the Porte St. Dominique, and reach the Porte St. Roch (formerly the Porte du Chamfleury, and only opened at plague times) and the Porte de la République. We soon note the unrestored portions, the site of the old Porte Limbert, and turn northward to the Porte St. Lazare. Before we reach this gate we may fitly make a digression, and in pious memory of a great Englishman, fare along the Avenue du Cimetière to the grave of John Stuart Mill, who with his wife lies buried within the cemetery under an elder-tree on the right and toward the end of Avenue 2. A plain stone slab bears the well-known inscription to Mrs. Mill's memory--the noblest and most eloquent epitaph ever composed by man for woman. It is pleasant to remember that Mill has left golden opinions of his gentleness and generosity behind him at Avignon. His house, a charming little hermitage approached by an avenue of plane trees not far from the cemetery, was sold in 1905, and a few relics were bought and still are cherished by the rare friends the somewhat self-centered philosopher made in the city. The present owner has preserved the library and study, where the "Essay on Liberty" was written, much as it was in Mill's days.