XF. IMPORT OF PROGRESS. E. W. CLAYPOLE. 



general way ; but when it comes to tracing and opening 

 special beds, then a specially accurate local survey must be 

 made by those interested. 



In presenting this report, it is my duty to remind the 

 Board that Prof. Claypole was commissioned by it for a 

 particular purpose, namely, to study the fossils of Perry 

 and Juniata counties, and to discover the locality and range 

 of each species in the pile of formations ; in other words, 

 to learn what genera and species of animal form, charac- 

 terize the different rock-deposits which outcrop along the 

 Juniata river. In the pursuit of this business he was com- 

 pelled to acquaint himself with the order of the rock- 

 deposits, and to define their upper and lower limits, and 

 their subdivisions. His attention was arrested near New 

 Bloomfield by the irregular conjunction of certain forma- 

 tions which were elsewhere separated by hundreds or thou- 

 sands of feet of intermediate deposits. The cause of this 

 irregularity is shown on the plates which accompany the 

 report, in the shape of two principal faults, or cracks in 

 the earth, on one side of which the rocks are lifted and on 

 the other side lowered, so as to bring into contact the edges 

 of formations which ought to be far apart, at the present 

 surface. 



In other parts of the county he found disturbances of 

 another kind interfering with his study of the fossils, viz : 

 a crumpling of the deposits sideways, increasing their ap- 

 parent thickness, and duplicating the same bed one or more 

 times. This led him to a remeasurement of the formation- 

 thicknesses. 



The result has been this preliminary descriptive report 

 on the structural geology of Perry county ; and it will be 

 noticed that only so much attention has been given to the 

 economic geology, the fossil iron ore beds, the limestone 

 quarries, and the worthless coal beds of Duncannon and 

 Mt. Patrick, as came in the way of the main pursuit, and 

 w;is necessary for the limitation of the formations. The 

 discussion of the utility of lime on soils and the table of 

 living plants were intended to be merely appendixes to the 

 report. 



