Gibralter is situated upon a point of land at the south of Europe, on the north side of the Straits of Gibralter, which forms a communication between the Atlantic and Mediterranean sea. It belongs to Great Britain, and is undoubtedly the strongest fortress in the world, and is supposed to be impregnable. The length, from[232] the Spanish line to the most southern point is three miles, and the circumference seven. No communication can be held between the garrison of this fortress, and the rest of Spain, owing to a strongly fortified line drawn for the purpose by the Spaniards. The town is defended on the water side by a line of ramparts forming a continued fortification from the north and perpendicular side of the rock, to the extremity of the Moors' wall, which was built about the year one thousand. This wall divides the rock into two equal parts, running from the water's side up a very steep ascent. Since the time this wall was built, fortifications have been carried entirely round the rock, and works cut into the interior on the perpendicular side, which renders them impregnable. Since this place was captured by the English they have excavated the rock, forming galleries and caverns of several thousand feet in length, and in case an enemy should carry the outer works, the besieged can retire to these subterraneous passages, and there hold out against an immensely superior force. These galleries are at an elevation of from 300 to 1300 feet above the surface of the plain below. They are arranged in tiers, each forming a battery, of which there are 23 in number. Were a general battery of all the embrazures to take place at the same time, it would afford one of the grandest spectacles in the world. In every place where it is possible to make an attack even with a small number of men, cannon are planted upon the surface of the rock, and these are at such an elevation, and the use of them so well understood, that[233] the object aimed at is hit with as much certainty as with a fusee. Should the lines near the water be carried by an enemy, they would have to dispute the ascent to the top of the mountain inch by inch, and should they even succeed in obtaining possession of the whole surface of the mountain, they would have to combat an army in the bowels of the rock against a thousand mines and other artifices, which would render the situation of the assailants very unsafe and dangerous. There are close quarters in the rocks for 1200 men, and provisions for three years, with a sufficient quantity of ammunition always stored there. Since the English took Gibralter in 1704, it has been repeatedly besieged but always without success. The combined forces of Spain and France laid siege to it in 1779, and after four years of the most strenuous and powerful efforts to reduce it, were obliged to abandon the project, and withdraw.