86 DOMAIN III. ARGILLACEOUS. 



artificial crystallisations : but that a ready-formed 

 stone, as large as the head, should stop in the 

 middle of a vertical wall, and have waited there, 

 till small particles of stone should come and sur- 

 round it, cement it, and fix it in that place, is a 

 supposition at once absurd and impossible. It 

 must then be considered as a thing demonstrated, 

 that these pudding-stones have been formed in a 

 horizontal position, or nearly so, and elevated 

 after their induration. What is the cause that 

 has elevated them? It is what, as yet, we are 

 ignorant of; but it is already one step, and that 

 an important one, to have found, among the pro- 

 digious quantity of vertical beds which are met 

 with in our Alps, some, which we are very cer- 

 tain have been formed in a horizontal position. 



" Even the nature of the substance which en- 

 velopes the pebbles of these pudding-stones, ren- 

 ders this fact more curious, and more decisive. 

 For if it was a misshaped and coarse paste, it 

 might be thought that these pebbles, and the paste 

 which cements them, were thrown pell-mell into 

 some vertical crevices, where the liquid part hard- 

 ened by drying. But on the contrary, the tissue 

 of this paste is of admirable regularity and fine- 

 ness ; it is a schistus, whose elementary laminae 

 are extremely thin, mixed with mica, and perfectly 

 parallel to the planes which divide the beds of the 



