1880.] -L^-L [Stevenson. 



Metallic iron 52.600 



Sulphur 0.018 



Phosphorus 0.116 



Insoluble residue 18. 140 



there being but .220 of phosphorus in 100 parts of iron. 



The very soft or granular ore was analyzed. It has the same character 

 as the last, except that, owing to the presence of the quartz pebbles, the 

 insoluble residue is very great. The proportion of phosphorus is .228 in 

 100 parts of iron. 



Three beds were seen in the area along the south-east slope of Powell 

 mountain beyond the North Fork gap. The highest one is thin and 

 contains only silicious ore. The second bed shows : 



Ore 1' 



Shale V 



Limestone and Ore 0' 5" 



Shale 0' 4" 



Ore 0' 5" 



Shale 0' 4" 



Ore 1' 



At 50 feet below this, the interval being filled with sandstone, another 

 bed was seen showing : 



Yery soft ore 1' 3" 



Hard ore , 1' 6" 



The ore in both of these beds is leaner than that seen in Poor valley and 

 on Wallen's ridge, but it can be mined very cheaply. These Powell 

 mountain ores show the fossils much more distinctly than do those in the 

 other localities and the forms are larger. Leptoecelia Jiemispherica, Strep- 

 tor hyncJms sudplana and the pygidium of a Galymene occur abundantly. 



The Medina Sandstone.— Thi?, was seen only on the crest of Wallen's 

 ridge near the head of the valley separating that ridge from Pjoor Valley 

 ridge. It is a moderately coarse, light gray sandstone, evidently more than 

 300 feet thick, and so far as obseiwed contains no fossils. 



The Lower Silurian Rocks. 



No rocks of this age appear in the Poor valley within at least 15 miles 

 west from the Big Stone gap; nor are they exposed between Wallen's 

 ridge and Powell mountain between North Fork and Little Stone gap ; nor 

 do they come to the surface along the south-east slope of Powell mountain 

 beyond that gap. But they are well exposed on the northerly face of Wal- 

 len's ridge and in Wallen's valley, which separates that ridge from Powell 

 mountain beyond the North Fork gap. 



Limestone is the prevailing rock and there is little reason to believe that 

 even the base of the limestone of II is reached at any exposure within the 

 area examined. With the limestone, shale is interstratified, which is some- 

 times fissile but often compact and not laminated. One cannot fail to note 



