122 GEOLOGICAL RECONNOISSANCE 



The rock which forms the immediate cliff on the Barren fork, above 

 Morrow's house, and extends down to the bed of that stream, is a very 

 rugged and cherty limestone. 



Some loose pieces of lead ore having been found in the bed of the Barren 

 fork, some shallow pits and shafts were sunk in the bluff above, into this 

 cherty limestone, and about 100 pounds of lead ore taken out from amongst 

 the red clay and loose chert, some of which will yield 70 to 80 per cent, of 

 lead. Here we have a further confirmation of the lead-bearing character 

 of this barren cherty limestone formation. 



This rock does not appear to be as thick here as further to the north, 

 since shale has been struck in Morrow's well beneath this rock. 



Some " gravel mineral" has also been found in the bed of the Barren 

 fork of the Illinois, near the mill, six miles from Evansyille. 



The fossiliferous limestone was again seen, three and a half miles from 

 Evansville, overlying dark ferruginous, and light-colored chert. 



The succession in Vineyard township is, therefore, approximately as fol- 

 lows : 



1. Fine-grained siliceous rock, approaching to the texture of whet- 



stones in its character. 



2. Limestone. 



3. Shale? 



4. Yellowish coarse sandstone. 



5. Finer grained schistose sandstone of the character of grindstone grit. 



6. Archimedes or other limestones. 



7. Dark shale rocks. 



8. Brown freestone. 



9. Shale. 



10. Fossiliferous chert. 



11. Fossiliferous limestone with marly and shaly partings. 



12. Chert, and 



13. Cherty limestone. 



14. Black shale. 



All of these strata belong to the millstone grit and underlying subcarbo- 

 niferous group. 



Soon after leaving Evansville, we ascended a high ridge, 550 feet above 

 the Barren fork, in the gap through which the road passes. 



On the north-west slope of this spur of*the Boston mountain range, the 

 outcropping ledges of rock are mostly sandstone and subcarboniferous lime- 

 stone, with some alternations of shale. In this side the Archimedes lime- 

 stone was observed at an elevation of 240 feet. On the south-east slope 

 of the mountain an immense mass of marly shale makes its appearance, 



