194 DOMAIN'X. 



indissoluble siliceous earth. 'Uniting' the pro- 

 ducts of these two operations, 100 grains of this 

 schistus were found to contain, Lime '61,45, 

 Silex 27,50, Magnesia 6,00, Argil ',$5, Iron 

 '1,42, Water, air, and loss 1,38. Total 100,00. 



"The layers of this schistus are intermingled 

 with layers of a fine sandstone; 1 but little cohe- 

 rent, and which resolves of itself in a white sand, 

 found in quantity at the foot of these same layers. 

 'The weak gluten, which unites these 'grains of 

 sand, is of a; calcareous nature. 



" These layers are a little bent; but their ge- 

 neral position, of those at least which are the 

 lowest, is vertical, excepting by a fe"w dfegrees, 

 in which they reciihe against the mountain. 

 There can be no doubt on the position of the 

 beds of these schisti, because they are exactly 

 parallel to the plates of which they are com- 

 posed. But these layers are cut here and there, 

 and at right angles, by clefts parallel to one an- 

 other, and which all bend alike, descending to 

 the S. W. under an angle of about 50 degrees. 

 These clefts leave intervals between them ; here 

 a foot, there only a few inches. When they are 

 observed at a distance, it is impossible not to 

 take them for divisions of the beds of the rock, 

 so important is it in these researches to see the 







Abject close, and observe it in detail ; for the in- 



