644 BOL 



Bdea. which was necessary to their nature.. Perhaps those 

 seas may have been heated by the effects of the volca- 

 noes, whose remains are scattered over the territory ; 

 for although great bodies of water cannot be sud- 

 denly fretted by a change of temperature, the shal- 

 lows immediately surrounding volcanic mountains 

 and isles have been known to mel f l "> -' ' 



tels sai' ; - - ' . F' IV -" OI ves ' 



K Kidx by their sides. Such shallows are 



always a grateful abode to fishes : there they flock 

 together in Humbert, and perhaps find more copious 

 supplies of food in the marine insects which the heat 

 conspires to propagate and diffuse. The atmosphere 

 -is likewise greatly heated by the fires of constant 

 volcanoes ; and it has been affirmed, that one of the 

 most productive islands in the globe is rendered so, 

 principally by the constant flames of eight volca- 

 noes. In this way, the temperature of the Veronese 

 territory may have anciently been augmented. It 

 is infinitely more difficult to explain how salt and 

 fresh water fishes are intermixed ; for although it 

 be very possible, that, by gradual and almost im- 

 perceptible transitions, they might be reciprocally 

 brought to live in either ; or successive generations, 

 by passing from greater or lesser degrees of saltness 

 or freshnes while in the ovular state, might habituate 

 the perfect animal to the change ; as we have not 

 witnessed the fact, we cannot maintain that it has 

 taken place. Still it is to be remembered, that some 

 fishes dwell in salt or fresh water indiscriminately ; 

 that we do not know whether confinement to one of 

 them only is destructive ; and that there is a minute 

 resemblance between the species of the same genera 

 which inhabit both. 



The presence of the sea, however, on the Vero- 

 nese territory, is not indispensible to the existence of 

 the fishes of Bolca. A volcano on the surface of 

 the earth may have been the sole agent. Some 

 philosophers affirm, that all volcanoes have a commu- 

 nication with the sea by subterraneous caverns. 

 Mount Vesuvius vomited quantities of water in 1538, 

 and in later times : and JEtna, in 1755, cast up salt 

 water, mixed with stones and sand. But we have 

 still more decisive proof, how essential volcanic agency 

 might be in producing the fishes of Bolca, from learn- 

 ing that vast quantities of a species of small fishes 

 have been discharged from the burning craters of 

 mountains in South America; sometimes in such ex- 

 traordinary numbers, that their putrefying bodies 

 threatened to create a pestilence in the land. Vol- 

 canic eruptions in the vicinity of the sea, or of lakes, 

 are commonly fatal to vast multitudes of fishes ; on 

 which account, those which issued from the Peruvian 

 mountains might have perished before being absorbed 

 by the craters. Pliny, in describing the fatal catas- 

 trophe wherein his uncle perished, remarks, that the 

 sea suddenly ebbed during the eruptions of Vesuvius, 

 and many animals remained dry on the sand : and 

 centuries afterwards, a similar phenomenon allowed 

 the inhabitants of the neighbourhood to collect the 

 fishes lying dead on the shore. During the rise of 

 new islands from the sea of the Greek Archipelago, 

 dead fishes continued to be thrown up during a whole 

 month on the sand : and an instance, still more no- 

 ted, was seen in 1742, at the port of Vera Cruz in 



C A. 



Mexico. A sudden agitation of the sea on the 19th 

 of October, threw down part of the wall of the city, 

 and threatened the vessels in the harbour with de- 

 struction. Next day incredible quantities of fishes 

 covered the beach, lying in henn, on each other; and 

 consist'^ ^ ma ny species altogether unknown to the 

 fishermen : nor were they confined to the vicinity 

 of the port, as the same appeared at the distance 

 of leagues from it. The heaps were so great, that, 

 to avert the danger of putrefaction infecting the 

 atmosphere, all the slaves of the place, and the crews 

 of the royal gallies, were employed in burying them in 

 the places where they lay. The like phenomenon was 

 renewed in the island of Sumatra, in the year 1755, 

 when an amazing multitude and variety of fishes, some 

 dead, others dying, were found on the shore. We arc, 

 therefore, entitled to maintain, that fishes may be 

 vomited from the crater of a volcano ; and to con 

 elude that volcanic eruptions are sometimes singular- 

 ly destructive of those in the surrounding seas. Dif- 

 ferent theories are entertained respecting the cause of 

 their death. Some naturalists conceive that a mephi- 

 tic vapour is suddenly diffused throughout the water, 

 which immediately becomes fatal to'the animals with- 

 in its sphere ; that they are involved in showers of 

 volcanic ashes, which then become the deposit of 

 their bodies, and the source, as in the case before us, 

 of their future preservation. The fishes of Bolca 

 have unquestionably perished by sudden death, as is 

 demonstrated by the half digested food in the sto- 

 machs of some of the most voracious. Those who 

 oppose the deposit being formed at the bottom of the 

 sea, maintain, that the fishes, once exposed on a dry 

 shore, might easily be covered and invested by show- 

 ers of ashes, which, while forming a crust around 

 them, would aid the absorption and evaporation of 

 the water ; and that their gradual accession is particu- 

 larly favourable to preserving the figure of the ani- 

 mals enclosed, from the superincumbent 'weight not 

 being sufficient to crush them. As the strata of Bolca, 

 along with fishes, contain the leaves of trees, terrestrial 

 plants, fruits, and flowers, and even some winged ani- 

 mals, this hill could not be at the bottom of the sea 

 when the deposit was formed, because the lightness of 

 leaves always buoys them up on the water. Volcanic 

 showers also are heavy enough to break them off the 

 trees, and are even capable of killing birds ; and that 

 peculiar odour emitted by the flags is improperly re- 

 ferred to an animal principle, for it should rather be 

 called bitumenous. The ashes discharged in forming 

 the new islands of the Archipelago were mixed with 

 much bitumen, which served as a gluten to bind them 

 together, consolidate them, and involve the substan- 

 ces which they covered. Those from an eruption 

 of Vesuvius in 1737, spread over the gulf of Ve- 

 nice, and at Zannichelli diffused a similar odour, 

 which assuredly, say the partizans of this doctrine, 

 could not be imparted by putrefying fishes. " Vol- 

 canic showers," in the words of Domenico Testa, 

 " having fallen on Bolca, destroyed and burned to- 

 gether, the fishes of the sea, the birds of the air, 

 the trees, and plants of the earth. Thus did an 

 eruption form that celebrated cemetery of fishes, 

 which for two centuries has equally been the admj-. 



Bolca. 



