At the commencement of the Second Empire the fortifications, as they then existed, possessed a circumference of something above thirty-three kilometres--approximately nineteen miles. The walls are astonishingly thick, and their _fossés_ wide and deep. The surrounding exterior forts "_de distance en distance_" are a unique feature of the general scheme of defence, and played, as it will be recalled, no unimportant part in the investiture of the city by the Germans in the seventies. A French writer of the early days of the last Empire says: "These new fortifications are in their ensemble a gigantic work." They are, indeed--though, in spite of their immensity, they do not impress the lay observer even as to impregnability as do the wonderful walls and ramparts of Carcassonne, or dead Aigues-Mortes in the Midi of France; those wonderful somnolent old cities of a glorious past, long since departed. The fortifications of Paris, however, are a wonderfully utile thing, and must ever have an unfathomable interest for all who have followed their evolution from the restricted battlements of the early Roman city. The Parisian has, perhaps, cause to regret that these turf-covered battlements somewhat restrict his "_promenades environnantes_," but what would you? Once outside, through any of the gateways, the Avenue de la Grande Armée,--which is the most splendid,--or the Porte du Canal de l'Ourcq,--which is the least luxurious, though by no means is it unpicturesque; indeed, it has more of that variable quality, perhaps, than any other,--one comes into the charm of the French countryside; that is, if he knows in which direction to turn. At any rate, he comes immediately into contact with a life which is quite different from any phase which is to be seen within the barrier. From the Revolution of 1848 to the first years of the Second Empire, which ought properly to be treated by itself,--and so shall be,--there came into being many and vast demolitions and improvements. Paris was a vast atelier of construction, where agile minds conceived, and the artisan and craftsman executed, monumental glories and improvements which can only be likened to the focusing of the image upon the ground glass. The prolongation of the Rue de Rivoli was put through; the Boulevards Sebastopol, Malesherbes,--where in the Place Malesherbes is that appealing monument to Dumas by Gustave Doré,--du Prince Eugène, St. Germain, Magenta, the Rue des Écoles, and many others. All of which tended to change the very face and features of the Paris the world had known hitherto. The "Caserne Napoleon" had received its guests, and the Tour St. Jacques, from which point of vantage the "clerk of the weather" to-day prognosticates for Paris, had been restored. Magnificent establishments of all sorts and ranks had been built, the Palais de l'Industrie (since razed) had opened its doors to the work of all nations, in the exhibition of 1855.