80 Prof. Bischof o?t Volcanos. 



solid state, that [is, whether in earlier times these masses rose 

 suddenly and continued to rise more and more slowly as they 

 gradually cooled, or wliether this gradually decreasing ratio 

 has always existed. We may, however, be allowed the remark, 

 that the slow elevation which still continues when the operation 

 of the vapour, as an elevating power, has long ceased, may be 

 regarded, according to what has been stated above, as the re- 

 sult of an expansion produced by the caloric disengaged from 

 the vapour during its condensation. For example, let us as- 

 sume that the solid crust of the earth in Scandinavia was 

 139,840 feet thick, that the expansion of this crust by heat 

 takes place in the same ratio as in earthen ware ; then, an ave- 

 rage increase of heat of 2°9 R. during the space of 100 years, 

 would be sufficient to effect an expansion of 4. 26 feet in a stra- 

 tum of the above-mentioned thickness. And this is the average 

 ratio of the rising of that country. 



Be the cause of the elevation of Scandinavia what it may, 

 this circumstance is remarkable, that in the southern part of 

 Sweden^ where the country, according to Nilson's statement, 

 sinks, secondary formations, viz. chalk, occur in great abund- 

 ance, while in the north of Sweden, as well as in Finland, the 

 gneiss-granite formation predominates. We must not, however, 

 attach too much importance to the connexion which appears to 

 exist between the elevation of the northern part of Szveden and 

 the prevalence of the latter formation, as Nilson* says, the 

 chalk also lies on gneiss, and less frequently on greywacke. It 

 is nevertheless remarkable that the granite island of Bor?ihoIm, 

 which is situated opposite to the sinking coast of Schonen, is 

 still in the act of rising, according to the observations of Forch* 

 hammer above alluded to. 



As regards the sinking of countries, there is no difficulty in 

 regarding it as the result of an elevation of neighbouring coun- 

 tries. Yet we can imagine many causes, independent of such 

 elevations, which may produce depressions. It does not, how- 

 ever, lie within the scope of these remarks to enumerate these 

 causes. 



It remains to consider the elevations of whole systems of 



* Petrificata Suecaua Form. Cretaceao, &c. 1827. P. 81. 



