UNIFORMITY OP CHANGE 437 



had been a sudden change from the Greek to the Italian 

 language in Campania. But if he afterwards found three 

 buried cities, one above the other, the intermediate one being 

 Roman, while, as in the former example, the lowest was 

 Greek and the uppermost Italian, he would then perceive the 

 fallacy of his former opinion, and would begin to suspect 

 that the catastrophes, by which the cities were inhumed 

 might have no relation whatever to the fluctuations in the 

 language of the inhabitants; and that, as the Roman tongue 

 had evidently intervened between the Greek and Italian, so 

 many other dialects may have been spoken in succession, and 

 the passage from the Greek to the Italian may have been 

 very gradual, some terms growing obsolete, while others 

 were introduced from time to time. 



If this antiquary could have shown that the volcanic 

 paroxysms of Vesuvius were so governed as that cities 

 should be buried one above the other, just as often as any 

 variation occurred in the language of the inhabitants, then, 

 indeed, the abrupt passage from a Greek to a Roman, and 

 from a Roman to an Italian city, would afford proof of 

 fluctuations no less sudden in the language of the people. 



So, in Geology, if we could assume that it is part of the 

 plan of Nature to preserve, in every region of the globe, an 

 unbroken series of monuments to commemorate the vicissi- 

 tudes of the organic creation, we might infer the sudden 

 extirpation of species, and the simultaneous introduction of 

 others, as often as two formations in contact are found to 

 include dissimilar organic fossils. But we must shut our 

 eyes to the whole economy of the existing causes, aqueous, 

 igneous, and organic, if we fail to perceive that such is not 

 the plan of Nature. 



I shall now conclude the discussion of a question with 

 which we have been occupied since the beginning of the fifth 

 chapter namely, whether there has been any interruption, 

 from the remotest periods, of one uniform and continuous 

 system of change in the animate and inanimate world. We 

 were induced to enter into that enquiry by reflecting how 

 much the progress of opinion in Geology had been influenced 

 by the assumption that the analogy was slight in kind, and 

 still more slight in degree, between the causes which pro- 



