The basement rock of Gibraltar is for the most part a greyish white or pale grey limestone, of compact and sometimes crystalline texture, arranged in beds, but in some places apparently amorphous. Above the limestone is a series of dark greyish blue shales with intercalated beds and bands of grit, sandstone, and limestone; and distributed here and there about the promontory are various limestone breccias, bone-breccias, and calcareous sandstones, as well as loose sand and debris. It is evident that the whole promontory has had an eventful geological history in comparatively recent periods. The limestone and the shales are both of Lower Jurassic age, but the rest of the formations are of much more ancient date. According to the researches of Professors Ramsay and Geikie (“Geology of Gibraltar,” in the Quarterly Journal of the Geological Society, London, 1878),the oldest superficial accumulation is the unfossiliferous limestone breccia of Buena Vista, which must have been formed under somewhat severer climatic conditions than the present, and when the rock had a wider area of low ground at its base. This period was probably followed by one with a genial climate, during which the promontory, if indeed it was not rather an isthmus between Europe and Africa, was clothed with vegetation and inhabited by a rich mammalian fauna, whose remains are still found in the Genista caves. Next there came a subsidence of a large proportion of the rock to the extent of 700 feet below the present level, the consequent erosion of ledges and platforms, and the formation of the calcareous sandstones which have incorporated shells of recent Mediterranean species. The process of depression was apparently interrupted by pauses. On its re-elevation, the land was again of greater extent than now; Africa and Europe were perhaps reunited, and the climate was probably genial. By a new depression the rock was brought into its present geographical relations.

Like most masses of limestone formation, the promontory of Gibraltar is honeycombed with caverns and subterraneous passages, and the Genista cave, already incidentally mentioned, is only one of the many to which it owes the title of the Hill of Caves. A special interest attaches to some of them for the palaeontological and archaeological remains which they yielded to the explorations of Captain Brome between 1863 and 1868. St Michael’s Cave, which is the most frequently visited by strangers, has its entrance about 1100 feet above the sea on the western face of the rock in the line of the Southern Quebrada. A rapid slope of earth gives admission to a hall 200 feet long by 70 feet high, the roof of which appears as if it were supported by massive stalactite pillars; and from this hall access is obtained to a series of four similar caves connected with each other by tortuous passages, the last cave being situated about 300 feet below the surface, and about 400 feet of travelling distance south by west from the entrance. The first of the four was called Victoria cave by its discoverer Captain Brome, and the three others, being more closely associated, received the common name of Leonora’s caves. “Nothing,” says Captain Brome, “can exceed the beauty of the stalactites; they form clusters of every imaginable shape—statuettes, pillars, foliages, figures. Even the American visitors have been compelled to acknowledge that, as regards beauty and picturesqueness, even the Mammoth Cave would not come near them.” The mammalian remains of the Genista cave have been investigated by Mr Busk (“Quaternary Fauna of Gibraltar,” in Trans, of Zool. Soc., vol. X. p. 2, 1877), and found to comprise specimens of a bear, probably Ursus fossilis of Goldfuss; a hyaena, probably H. crocuta or spelcea] various species of cats, from the size of a leopard to that of a wild cat; a rhinoceros similar to the species found in the valley of the Thames; two forms of ibex; and the hare and the rabbit. No trace has been discovered of Rhinoceros tichorinus, of Ursus speloeus, or of the reindeer, and the only relic of the elephant as yet registered within the peninsula is a perfect specimen of the penultimate upper molar tooth of Elephas antiquxιs. For further details see James Smith of Jordanhill “On the geology of Gibraltar,” in Quart. Journ. of G eοl. Soc., vol. ii., and G. Busk and Hugh Falconer “On the Fossil Contents of the Genista Cave,” in Quart. Jourιι. of Geοl. Soc., vol. xxi., reprinted in Falconer’s Pedoeontological Memoirs, London, 1868.

To the voyager entering the straits the rock presents a bare and almost barren aspect, especially when the summer suns have dried up the verdure; but as he approaches he discovers a considerable clothing of vegetation, and closer acquaintance reveals the existence of an extensive flora. Here and there a grassy glen gives shelter to a group of trees, and the villas of the English residents are surrounded with luxuriant gardens and copses. Dr E. F. Kelaart in his Flora Calpensis (London, 1846) enumerates upwards of 400 flowering plants and ferns as indigenous to Gibraltar, and about fifty as introduced. Of the former a few appear to be species peculiar to the rock. White poplars, the cotton-tree, the pepper-tree or pimenta, the ilex, and the pine are the most noticeable of the larger trees; the bella-sombra (Phytolacca dioica), introduced by General Don, the aloe, and the prickly pear are common; and on the eastern side of the rock the dwarf palm (Chamoerops humins') covers large areas. Among the fruit trees, which, however, are cultivated rather for ornament than for profit, may be mentioned the almond, the olive, the orange, the lemon, the pomegranate, the fig, and the loquat. In January and February many portions of the rock present a charming sight from the profusion and beauty of the wild flowers. The fauna of Gibraltar is naturally poor,—rabbits, foxes, partridges, pigeons, and woodcocks being the principal species. The little Barbary apes, of which every schoolboy has heard, but which not every resident in Gibraltar has seen, are few in number, not more than twenty perhaps, and they usually inhabit the higher and eastern parts of the rock, except when they are driven towards the lower grôunds by the cold winds from the north-east. They then do a little damage to the fruit trees; but they enjoy impunity as perfect as that of the storks in Holland or the ibis in Egypt. As to its climate Gibraltar belongs to the subtropical zone, with a dry summer and a rainy season in winter. More than half the rainfall of the year, which only amounts to about 28 or 30 inches, occurs in November, December, and January; and the three months of June, July, and August are hardly refreshed by a shower. The temperature is subject to frequent disturbances: from 93° to 87° is the highest reached (July), and 43° the lowest (February), and the mean for the summer months is from 74° to 79°. In summer the heat is tempered by a sea-breeze which blows from about 10 a.m. till shortly before sunset. Easterly winds or levanters are common from July to November, and during their prevalence every living creature seems to suffer. Heavy dews and thick fogs occur in autumn, and are as disagreeable as they are unhealthy. In the early part of the present century Gibraltar was notoriously filthy and ill-drained, and epidemic diseases committed great ravages from time to time; but great improvements have been effected, especially through the sanitary com· mission instituted in 1865. The inhabitants were formerly dependent on the rainfall for most of their water supply, the springs in the rock being both scanty and brackish; but in 1869 an abundant source of fairly good water was found to exist under the sands of the North Front, and pump3 and conduits have been constructed for its distribution. In 1876 the quality of the water was reported to be deteriorating. Besides the private tanks, still numerous throughout the town, there are eight bomb-proof cisterns for rain-water, of a total capacity of 40,000 tons. The navy tank, for the supply of ships, holds from 9000 to 11,000 tons.

Gibraltar is emphatically a fortress, and in some respects its fortifications are unique. On the eastern side the rock needs no defence beyond its own precipitous cliffs, and in all other directions it has been rendered practically impregnable. Besides a sea-wall extending at intervals round the western base of the rock, and strengthened by curtains and bastions and three formidable forts, there are batteries in all available positions from the sea-wall up to the summit 1350 feet above the sea; and a remarkable series of galleries has been hewn out of the solid face of the rock towards the north and north-west. These galleries have an aggregate length of between 2 and 3 miles, and their breadth is sufficient to let a carriage pass. Port-holes are cut at intervals of 12 yards, so contrived that the gunners are safe from the shot of any possible assailants. At the end of one of the galleries hollowed out in a prominent part of the cliff is St George’s Hall, 50 feet long by 35 feet wide, in which the governor was accustomed to give fêtes. Alterations, extensions, and improvements are continually taking place in the defensive system, and new guns of the most formidable sort are gradually displacing or supplementing the old-fashioned ordnance. The whole population of Gibraltar, whether civil or military, is subjected to certain stringent rules. For even a day’s sojourn the alien must obtain a pass from the town-major, and if he wish to remain longer a consul or householder must become security for his good behaviour. Licences of residence are granted only for short periods—ten, fifteen, or twenty days—but they can be renewed if occasion require. Military officers may introduce a stranger for thirty days. A special permit is necessary if the visitor wishes to sketch.

Though the town of Gibraltar may be said to date from the 14th century, it has preserved very little architectural evidence of its antiquity. Rebuilt on an enlarged and improved plan after its almost complete destruction during the great siege, it is still on the whole a mean-looking town, with narrow streets and lanes and an incongruous mixture of houses after the English and the Spanish types. As a proprietor may at any moment be called upon to give up his bouse and ground at the demand of the military authorities, he is naturally deterred from spending his money on substantial or sumptuous erections. The area of the town is about 100 acres. The public buildings comprise the cathedral of the Holy Trinity, a poor imitation of Moorish architecture; the governor’s house, formerly a Franciscan monastery and still familiarly known as “The Convent the exchange; the court-house; the civil hospital; the revenue offices; and the garrison library,planned by Colonel Drinkwater in 1793. The library has excellent readingrooms, and contains from 40,000 to 45,000 volumes. At the north-east corner of the town stand the remains of the Moorish castle. Towards the south the lower grounds are occupied by the Grand Parade and the Alameda Gardens, laid out by General Don in 1814; and beyond these are the old convict establishment, the dockyard, and the new-mole parade. Further south, at Rosia, is the naval hospital, erected in 1771.

Gibraltar has been a free port since the year 1705,—a distinction which it owes in part to the refusal of the emperor of Morocco to allow the export of materials for the fortifications unless his subjects obtained full liberty of trade. In the early part of the present century the commercial activity of the little colony was remarkably great. While the average value per annum of British manufactures exported to the rest of Spain during the ten years from 1831 to 1840 was less than ,£385,000, the corresponding average for Gibraltar was more than £486,000; and in the year 1840 the ratio of Spain and Gibraltar was £404,252 to £1,111,176. Since that date there has been comparatively little advance,—the average annual value of all the British and colonial produce and manufactures for the ten years from 1868 to 1877 being £1,074,785. Besides the legitimate trade fostered by the demands of the garrison and the neighbouring cities of Spain, Gibraltar has long had a large contraband traffic especially in tobacco and Manchester goods. Mainly carried on by Spaniards, it continued to thrive in spite of the exertions of the Spanish authorities, and is now kept down mainly by the action of British officials. About 1200 tons of tobacco are sold annually in the Jews’ Market; no fewer than eleven houses import upwards of 1000 tons annually; and its manufacture and manipulation give employment, it is said, to about 1550 persons. Fully two-thirds of the tobacco comes from Calcutta and other Indian ports. “Wool, grain, and wax from Morocco, fruit, wine, oil, and other produce from Spain, are sent to Gibraltar for transhipment to England, France, Germany, Belgium, Holland, Portugal, America, ports in the Mediterranean, India, and China.” As a port of call, the Bay of Gibraltar has recently increased in importance. Upwards of 5000 vessels enter the port annually, and of these more than half are propelled by steam. The average annual tonnage of the ships that entered between 1871 and 1875 was 2,069,508; and of this no less than 1,594,174 was British. Quarantine was established in 1830. By the shipping act of 1868 the governor was empowered to remove from the register any vessel guilty of a violation of the Spanish revenue laws discreditable to the British flag. In 1865 a duty was imposed on wines and spirits. Great commotion was caused among the mercantile population of Gibraltar in 1871 by a proposed customs ordinance, framed for the suppression of the smuggling. One of its chief provisions was that no tobacco should be exported or imported in vessels of less than 100 tons burden or in packets of less than 80 lb.

The population of Gibraltar in 1840 was 15,554, of whom 11,313 were British subjects and 4241 aliens; and by 1850 it had increased to 15,823, with 3641 aliens. In 1860 the civil population, including foreigners visiting the garrison, amounted to 17,647; but the number of resident inhabitants was only 15,467. According to returns for 1872 the total population was 18,695 (8969 males and 9726 females), the aliens numbering 2241 and the military 6521. The death-rate of the civil population varies from 25 to 31 per thousand, but it is almost always exceeded by the birth-rate. During the five years 1871-1875 the average number of births per annum was 592 ’ 4, and of deaths 538 ’ 2. Besides the natives, who themselves are of various origin, there are always in the town considerable numbers of Spaniards, Portuguese, and Italians, as well as stray representatives of almost every nationality engaged in the trade of the Mediterranean. Though by the treaty of Utrecht it was specially bargained by Spain that “no leave shall be given under any pretence whatever either to Jews or Moors to reside or have their dwelling in the town of Gibraltar,” the native Jews by 1844 numbered no fewer than 1385.

The greater part of the population is Roman Catholic, but full religious liberty is of course enjoyed. The church of the Holy Trinity was constituted to be a cathedral and bishop’s see of the Church of England in 1843. The Wesleyans and the Presbyterians have places of worship. St Andrew’s, the new Presbyterian church, was built by the Free Church of Scotland in 1854. A proposal for concomitant endowment of “church bodies for the Anglican and Roman Catholic communities” with the annual sum of £500 was made by the governor in 1876, but it was not sanctioned by parliament. An annual grant to this amount is made to both bodies, but the Government no longer keeps the cathedral in repair. The Roman Catholic bishop of Antinoe is vicar apostolic of Gibraltar.

Gibraltar was long an ill-managed and expensive colony; but its expenditure is now sometimes even less than its revenue. During the five years from 1871 to 1875 the average expenditure, increased by several unusual items, was £43,988; and the average income was £42,464. For 1877 the expenditure was £41,585, or £1739 more than the income. The chief sources of the revenue are the port and quarantine dues, the excise on the consumption of wines and spirits, and the ground and house rents,—the three departments yielding respectively on the average from 1871 to 1875 £11,011, £11,512, and £6,206. It is worthy of note that the ground and house rentals have increased from £5629 in 1871 to £7078 in 1875. Among the heavier items of outlay are the governor’s salary, which amounts to £5000 per annum, and the judicial and ecclesi astical expenses, which were, on an average from 1871 to 1875, respectively £3909 and £1061. The total cost of the military establishment was, on the average of four years from 1869 to 1873, £315,454,—of which £250,340 was the average cost of the regular troops, £1610 for the jails, and £19,293 for the barracks. The convict establishment was abolished in 1875. At that date it contained 238 prisoners, who were managed on the associated system; and grievous complaints were made of the difficulty of maintaining satisfactory discipline.

History.—Gibraltar was known to the Greek and Roman geographers as Calpe or AIybe, the two names being probably corruptions of the same local (perhaps Phoenician) word. The eminence on the African coast near Ceuta which bears the modern English name oi Apes’ Hill was then designated Abyla; and Calpe and Abyla, at least according to an ancient and widely current interpretation, formed the renowned Pillars of Hercules (Herculis columnae, 'Hpaκλdoυs στ⅞λαι) which for centuries were the limits of enterprise to the seafaring peoples of the Mediterranean world. The strategic importance of the rock appears to have been first discovered by the Moors, who, when they crossed over from Africa in the 8th century, selected it as the site of a fortress. From their leader Tarik ibn Zeyad it was called Gebel Tarik or Tank's Hill; and, though the name had a competitor in Gebel at Futah or Hill of the Entrance, it gradually-gained acceptance, and still remains sufficientlyrecognizableinthe cor-nιpted form of the present day. The first siege of the rock was in 1309, when it was taken by Alonzo Perez de Guzman for Ferdinand IV. of Spain, who, in order to attract inhabitants to the spot, offered an asylum to swindlers, thieves, and murderers, and promised to levy no· taxes on the import or export of goods. The attack of Ismail ben Ferez in 1315 (2d siege) was frustrated; but in 1333 Vasco Paez de Meira, having allowed the fortifications and garrison to decay, was obliged to capitulate to Mahomet IV. (3d siege). Alphonso’s attempts to recover possession (4th siege) were futile, though pertinacious and heroic, and he was obliged to content himself with a tribute for the rock from Abdul Melek of Granada; but after his successful attack on Algeciras in 1344 he was encouraged to try his fortune again at Gibraltar. In 1349 he invested the rock, but the siege...