Quebec, from its situation and the care with which it has been fortified, is a very strong town, and considered the chief bulwark of British America. On the summit of the lofty headland just described stands the citadel. The rock consists of gray granite mixed with quartz crystals, and a species of dark-coloured slate. About forty acres are here covered with works, carried to the edge of the precipice, and connected by massive walls and batteries with the other defences of the place. The main body of the fortress, however, consists of the upper town, whose fortifications enclose a circuit of about two miles and three quarters. The face of the hill towards the river is so precipitous, that it requires only a common wall to protect it, though the gate leading from the lower town is defended by heavy cannon, and the steep approach by Mountain-street is enfiladed and flanked by many guns of large calibre. As the declivity towards the interior and the Plains of Abraham does not present the same abrupt face, but descends by successive ridges, it has been strengthened by a series of regular works, including ditch, covered way, and glacis, with some exterior defences to obstruct the approach of an enemy. It seems probable, therefore, that the place would hold out against any attack, till the approach of the rigorous winter should compel the assailants to raise the siege. The upper town, which these fortifications enclose, forms the chief part of Quebec, and the residence of all the principal inhabitants not engaged in trade. It is a tolerably handsome old-looking town; the houses being mostly of stone, partly roofed with tin. The streets are well paved, and in some instances macadamized, but they are much too narrow, as the broadest does not exceed thirty-two feet. St. Louis-street, the almost exclusive residence of the fashionable circle, has been lately adorned with several elegant mansions. The public buildings are commodious and substantial, without much pretension to architectural ornament. The Castle of St. Louis, a large, plain baronial-looking edifice, forms the dwelling of the Governor. It comprises a space of four acres, once fortified; but the great extension of the works has rendered its walls superfluous, and they are allowed to go to decay. The apartments are large and commodious, and the veranda commands a magnificent vista up the river. Adjoining is a spacious structure, once occupied by government offices, now chiefly employed for public entertainments. The enclosure contains two excellent and well-cultivated gardens.