1846.] Geological, of a trip to Carhondale. 6 



near enough the road to have their stratification observ^able, it 

 was, in a large majority of cases, unconformable, — different de- 

 positions forming not unfrequently three or four angles in the 

 same rock! The old red sandstone does not vary widely in its 

 lithological characteristics, from the rocks of the Portage and 

 Chemung groups. The greater sterility of its soils, is due proba- 

 bly, partly to the thinning out of the northern drift, and partly to 

 elevation. All these rocks are deficient in the lime necessary to 

 a highly luxuriant vegetation, and particularly to the more valua- 

 ble grains. To the two first named groups, it is partially sup- 

 plied by the drift alluded to. 



This group is remarkably destitute of fossils. For miles my 

 eye sought in vain, on the constantly exposed surfaces of the 

 rock, for the faintest trace of a cypricardite, or those fern-like 

 forms found in the quarries of Montrose, — or in fact, for any 

 fossil whatever. 



The ascent and descent of the Tunkhannock mountain occupy 

 four miles. Its ragged declivities give frequent proof of stupen- 

 dous convulsions, in its masses of rock, broken and thrown to- 

 gether in the wildest possible confusion. On its northern decliv- 

 ity, I first noticed boulders of cornstone, — those accretionary 

 masses of slate and lime, stained externally to a dark umber color, 

 which gives them provincially the name of " nigger heads." 

 From the southern base of the mountain to near Carbondale, it 

 is comparatively level. 



After traveling the " New Turnpike " a few miles, you com- 

 mence following Fall Brook down a mountain gorge, deeping as 

 you advance, cut out in the " old red sandstone." Finally from 

 the narrow chasm, the scene of many a former robbery and out- 

 rage, you descry, through the tree tops, the white masses of the 

 "conglomerate rock" capping the adjacent summits, and looking 

 like the battlements of ancient castles. So great is the dip of 

 the conglomerate, that the rapidly descending road soon enters 

 upon it, and its sides are strewed with vast blocks, resembling in 

 size and shape those of the red sandstone before described. One 

 magnificent slab nearly ten feet square, and over three feet thick, 



