50 SLATE DEPOSITS AND INDUSTRY OF UNITED STATES. 
TECHNICAL DESCRIPTION OF A SLATE QUARRY. 
The following outline of a description of a slate quarry for economic purposes is 
proposed as covering the features of practical geological and economic importance, 
aside from the ordinary statistical matters as to amount and value of product, num- 
ber of employees, etc. : 
Quarry name or number. 
Location (exact). 
Geological formation as given on the geological map. 
Distance from railroad and means of transporting product. 
Diagram of plan of quarry to scale. 
Depth of quarry. 
Dimensions of working face. 
Distance and direction of dumps from working face. 
Means of drainage. 
Number of inclines or of horse derricks. 
Number of slate-trimming machines. 
Kinds of slate produced. 
Thickness of good and bad beds in natural order. 
Diagram showing course of beds. 
Strike and dip of beds. 
Strike and dip of cleavage. 
Strike and dip of strike joints. 
Strike and dip of dip joints. 
Strike and dip of diagonal joints. 
Strike and dip of grain. 
Strike and dip of shear zones. 
Location and diameter ot posts. 
Proximity of dikes. 
Course and thickness of veins. 
