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good deal embarrassed in his attempt tosustain it. His assertion, that the gra-nite of the Pyrenees is higher than thelimestone, is followed by an admission thatthe limestone also is very high, sometimeshigher than the granite. He accounts forthis by assuming, that the granite is themore perishable of the two, and by sup-posing that it must have been the higherformerly, though the lower now.

The secondary ridge of the Jura ishigher than the primitive ridges of theVosges and Bretagny.

Mont Blanc a , the highest mountain inEurope , is said not to consist of granite.Be this as it may, its summit is only 128feet higher than that of Mont Rosa com-posed of stratified rocks.-

The principal heights of the Apennines are of secondary limestone.

In the British islands the principal emi-nences, Ben Nevis , Snowdon, the rocks ofKillarney , and the mountains of Cumber-land, are composed either of porphyry

* Saussure’s Voyages, § 2135 . Playfair’s Illustr. p. 200.