B O L 



641 



B O L 



poorte ; and a fourth towards Heusden, called St 

 John's gate. It is defended by a castle, callediPapen 

 Briel ; by the fo-t of Crevecceur, near the Meuse ; 

 the large fort ot Isabella ; and a small fort towards 

 Brabant, called St Antoine. The town is regularly 

 fortified, and its walls are flanked by seven bastions. 

 The approaches to it by land are on causeways, and 

 by water at three gates, called the Grand Hekel, the 

 Petit Hekel, and the Boom. The cathedral, built 

 in 1366, is one of the finest edifices in the Low 

 Countries. Its wooden tower, which was so lofty as 

 to be seen all the way from Antwerp, was support- 

 ed by four stone pillars, but was destroyed by light- 

 ning in 1584% There were formerly other four church- 

 es, but three of them are now used as warehouses. 

 When this town belonged to the Catholics, it con- 

 tained 16 monasteries. The monastery of the Jesuits 

 is now the governor's palace. There is likewise in 

 this city a college, and a town hall which is an exact 

 miniature of that of Amsterdam. There are here 51 

 stone bridges, and 8 made of wood. The adjacent 

 country can be easily laid under water, and sometimes 

 in winter the town can be approached only in boats. 

 The principal manufactures of Bois-le-Duc are linen 

 cloths, needles, knives, and several articles of iron 

 manufacture. Population 9600. East Long. 4 

 S&, North Lat. 51 W. (q) 

 BOKHARA. See Bucharia. 

 BOLABOLA, or Borabora, one of the Socie- 

 ty Isles, in the Southern Pacific Ocean, discovered 

 by Captain Cook in July 1769. It is about seven 

 leagues in circumference, and is surrounded with a reef, 

 nearly full of productive and populous islets. As its 

 shores arc rough and precipitous, it has only one har- 

 bour. A lofty double ptuked mountain rises in the 

 centre of the island. This mountain is barren on the 

 east side, but has bushes and trees on its craggy 

 parts. The lower grounds towards the sea are co- 

 vered with cocoa, palms, and bread fruit trees. It is 

 said that the first inhabitants of Bolabola were male- 

 factors banished from the neighbouring isles, that the 

 fame of their military talents increased with their num- 

 bers, and that they gradually extended their conquests 

 over the other islands. West Long. 1.51 52', North 

 Lat. 16 32' 30". See Missionary Voyage, Introd. 

 p. 4). (./) 



BOLCA, Mount. About eighteen or twenty 

 miles north-east of the city of Verona, there is a small 

 village called Bolca, from which a mount, or hill, re- 

 ceives the same appellation. The village itself is not 

 <if sufficient consequence to merit a particular descrip- 

 tion, but it is otherwise with the hill, for in its sub- 

 stance are contained some of the most remarkable na- 

 tural productions which the world affords. 



Around Mount Bolca, and throughout the territo- 

 ry of Verona, unequivocal volcanic remains demon- 

 strate the prevalence of subterraneous eruptions, and 

 also that the whole must have once been covered by 

 the sea. Numerous petrifactions of plants, shells, and 

 marine animals, are dispersed in the earth, but fre- 

 quently in such an arrangement, that beds in one dis- 

 trict are confined to certain species unmixed with 

 others, while the same peculiarity is observed in dis- 

 tricts more remote. In the mountains, whereof Bolca 

 :% one, there have been found 27 genera of Testacea, 



VOL. III. PART IV. 



hitherto unknown ; and not less than 200 species of 

 petrified shells have been dug from the tufa, marbles, 

 and basalts, of which the neighbouring territory is com- 

 posed. By a wonderful accumulation, shells, whose 

 animals inhabited different seas and different climates, 

 are collected together in the same heap, along with 

 those which never retreat to water. There are also 

 many petrifactions of zoophytes, consisting of the 

 articulations of asterix, clusters of corals, and madre- 

 pores ; and in this unaccountable aggregate, the parts 

 of terrestrial quadrupeds, of birds, and of insects, arc 

 not wanting. The bones of huge elephants, stags, 

 and bears, and likewise those of an intermediate tribe, 

 the phocae, have betn discovered. Basaltic columns 

 of various kinds are seen on Mount Bolca, and in the 

 neighbourhood, differing not only in structure, but 

 in the proportions of their elementary parts. Their 

 figure is hexagonal, pentagonal, quadrangular, and 

 even triangular ; and their position is generally per- 

 pendicular to the horizon ; but at San Giovanni d'l- 

 larione they exhibit a degree of obliquity, as if some 

 disturbing cause had altered their position. Burnt 

 earth, scorix, lava, and other volcanic productions, are 

 scattered about the Purga di Bolca ; and the hill itself, 

 barren of vegetation, is covered with earth intermixed 

 with animal and vegetable remains. These circum- 

 stances, added to the natural phenomena which will 

 come under our consideration, plainly shew, that the 

 tract environing Mount Bolca has been subject to 

 volcanic eruptions, and that the sea has covered it at 

 some very remote period. At present, the nearest 

 shore is fully fifty miles distant from its base. 



Part of what passes by the general name of Mount 

 Bolca, is situated at a short distance from the real 

 hill, and called Lastrara ; so that, according to the 

 strictest topography, they should be separated : but 

 no such division being spoken of when those who 

 precede us treat of the productions of the place, we 

 shall follow their example, in considering Bolca and 

 Lastrara as synonymous. 



All the fossils of the Veronese territory are incon- 

 siderable when compared with innumerable petrified 

 fishes found in Bolca, where it would seem as if the 

 whole seas and rivers of the globe had concurred in 

 depositing their contents. Those of Europe, Asia, 

 Africa, and America, are huddled together in one 

 confused heap : the fishes of the torrid zone are mix- 

 ed with those of temperate climates ; those of fresh 

 water rivers with those of the most extensive seas ; 

 and all differing in habits, structure, and properties. 

 Large masses of stone, detached and unconnected 

 with the ordinary substance of Mount Bolca, lie im- 

 bedded in the side of the hill, 1000 feet above the 

 level of the sea. Quarries penetrating into these, 

 have exposed the fossil fish to view. The 8tone con- 

 taining them is calcareous, of a schistose structure, 

 and susceptible of being split into flags, or laminse, 

 of various thickness and dimensions ; and it has been 

 denominated by mineralogists a marl or marley schist. 

 It is of a whitish, yellowish colour, or of a bluish grey, 

 and some of it is quite black. Its hardness, though 

 of different degrees, is such as commonly to yield to 

 the knife, but not to the nail ; and it has one characte- 

 ristic peculiarity, which consists in emitting a peculiar 

 fetid odour on being struck, or rubbed, compared to 

 4 M 





