Geological Travels in Hungary. 259 



ures, with their regular dip, gives them more the appear- 

 ance of gray wacke, than I have any where else seen ; for 

 mica is rare in the slaty clay of most other coal measures. 

 Our immense coal field above Pittsburg is 30 or 40 miles 

 distant from Bedford, the termination of the transition forma- 

 tion, which space is occupied by secondary limestone full 

 of shells, and sandstone, on the back of which the coal crops 

 out. 



M.Reudant found Gres houillier (coal measures) occupy 

 ing the greatest part of the north and summit of the Carpa- 

 thian mountains. I once went thirty or forty leagues from 

 Villiczka, across the Carpathians, but saw nothing that 

 1 could call coal measures or Gres houillier, but immense 

 beds of transition. From a note in page 171 of the 3d vol- 

 ume of M. Beudant's work, where he found the specimens 

 collected by M. Brongniart, in the Appenines, exactly to re- 

 semble the Gres houillier of the Carpathian mountains, I sus- 

 pect that what he calls Gres houillier,! have been in the prac- 

 tice of calling gray wacke, having passed the Appenines. in 

 seven or eight different places, without meeting any coal 

 measures, and having always considered them from Genoa 

 to Florence, to consist almost entirely of transition.* 



M.Beudani takes no notice of the regular dip of the trans- 

 ition rocks which I have always been led to consider as the 

 most evident and distinguishing line of separation between 

 them, and the secondary or horizontal class of rocks. This 

 is perhaps a necessary consequence of the confused state of 

 European stratification; it is only in the top of the secondary 

 hills or mountains that you can discover the horizontality 

 of the secondary, for the stratification is so deranged on the 

 sides that the dip is in all directions, and at all angles. One 

 of the advantages which the geoloj^ist enjoys in the United 

 States, in consequence of the regularity and undisturbed 

 stratification, is to be convinced of the real position of all 

 the rocks, at the first glance, with their dip and direction, 

 and to have no doubts concerning their actual and natu- 

 ral relative positions. 



*VVhen I go home I shall send to the Society specimens of the secondary, 

 compact limestone, of the coal fields above-mentioned, as well as specimeBs 

 of the Appenines, as they are all at Philadelphia, besides the suite of Italian 

 rocks which I srayc to the academy. 



