4 CONTENTS AND ILLUSTRATIONS. 
Part II. Slate Deposits of the United States — Continued. Page. 
Merriman's recent tests of slates 122 
Comparative characteristics of slates 124 
Statistics of production, imports, and exports 125 
Bibliography 138 
Glossary of Geological and Slate-quarry Terms 146 
Index 149 
ILLUSTRATIONS. 
Page. 
Plate I. Map showing location of slate deposits 5 
II. .1, Red slate with bed of limestone and green slate; B, Bed of sand- 
stone resting on slate 18 
III. Slate syncline at West Castleton, Vt 18 
IV. Plicated and faulted beds in slate 20 
V. A, Quartzite beds in overturned folds in slate; B, Quartz veins in 
slate 22 
VI. Slip cleavage after slaty cleavage 26 
VII. Shear zones 30 
VIII. Map showing Arkansas slate area 52 
IX. Sketch map showing location of slate deposits of Montgomery-Polk 
County slate district, Arkansas 54 
X. Geologic map of the Placerville slate district, California 56 
XL A, Thin section of Brownville, Me., slate; B, Cleavage banding 64 
XII. Merrill quarry at Brownville, Me 66 
XIII. Old Bangor quarry (north -north east end), Pennsylvania 76 
XIV. Old Bangor quarry (south-southwest end), Pennsylvania 76 
XV. Derricks and carriers, Old Bangor (marry, Pennsylvania 78 
XVI. Map of Slatingtou quarries, Pennsylvania 80 
XVII. Blue Mountain quarry, near Slatington, Pa 82 
XVIII. Eureka quarry, near Slatington, Pa 82 
. XIX. Removing the ' ' ribbon, ' ' Slatington, Pa 84 
XX. Map of quarries in New York and Vermont slate belt, south part. .. 88 
XXI. Map of quarries in New York and Vermont slate belt, north part. .. 88 
XXII. Sections across New York and Vermont slate belt 90 
XXIII. Quarry diagrams, New York and Vermont slate belt 92 
XXIV. Quarry diagrams, New York and Vermont slate belt 96 
XXV. Slate syncline at West Pawlet, Vt 98 
Fig. 1. Diagram, after Gosselet, showing relations of cleavage and bedding... 23 
2. Diagram of cleavage banding 32 
3. Diagram showing divergent strike of bedding and cleavage 43 
4. Map of slate region in Maine 61 
5. Map of slate prospects in Frederick and Montgomery counties, Md ... 68 
6. Sketch of anticline in Provident Slate Company's quarry, near Slating- 
ton, Pa 82 
7. Sketch of anticline in old quarry north of Slatington, Pa 82 
8. Sketch of syncline at William Hughes's quarry, Slatington, Pa 83 
9. Sketch of folds at Eureka quarry, near Slatington, Pa 83 
10. Microscopic drawing of Peach Bottom slate 87 
11. Diagram showing structure at Vermont Black Slate Company's quarry, 
near Northfield, Vt ___ 91 
12. Map of slate region in Buckingham and Fluvanna counties, Va 112 
13. Map showing location of Snowden quarries, Amherst County, Va 116 
14. Map of slate prospects in Fauquier County, Va 117 
15. Map of slate region about Martinsburg, W. Va 120 
