of Devonshire and Cor?nvall. 107 



Ramond has likewise met with this breccia in the Pyrenees.* He 

 describes it by the name of " bandcs " formed of a heterogeneous 

 mixture in irregular veins, occurring between the fundamental gra- 

 nite, and the secondary and tertiary mountains. Other travellers 

 have observed it in similar geological situations, in the Palatinate, 

 Saxony, Bohemia, and particularly in Siberia, where it is stratified, 

 and where jasper constitutes one of the principal elements of \\..\ 



An indefatigable artist, the beauty of whose descriptions Is not 

 Inferior to the graphic charms of his pencil, has proved, that a tra- 

 veller, without being a profound mineralogist, may, if guided by a 

 spirit of observation, collect materials very useful to those who know 

 how to employ them. Vivant Denon, in noticing the mountains 

 on the road from Keneh to Cosseir on the red sea, says, " at day- 

 " break we found the appearance of the country changed ; the 

 " mountains that we had passed the day before were rocks of free- 

 " stone ; these were of puddingstone, being a mixture of granite, por- 

 " phyry, serpentine, and other primitive species, aggregated In green 

 *' schistus. The vallies continued to grow narrower, and the rocks 

 *' on every side more lofty. At noon we had reached the first half 

 " of our journey, in the midst of fine rocks of breccia, which would 

 " be very easy to work if it were not for the great distance from any 

 " supplies of provisions : the portions of this granite, of which this 

 *' breccia is composed, shew, that the primitive mountains are not far 

 " distant.":!: 



With regard to the elevation, and abutting of the secondary and 

 tertiary strata as they approach the primitive rocks, Saussure and 



* Voyages au xMont Perdue, p. 197, 359, 205, &c. 

 + Kirwau's Geological Essays, 229. 



+ Voyage dans la basse et haute Egypte, tome I. p. 292 ; or English Translation, 

 Tol. II. p. 340. 



o2 



