LIST OF ILLUSTRATIONS. 



PLATES. 



Guide to the Study of the Collections in the Section of Applied GeolocxY: 

 The Nonmetallic Minerals. 



By George P. Merrill. 



Facing page. 



1. View showing wall and rail cases and installation of nonmetallic minerals 



on gallery of southwest court, U. S. National Museum. Looking west.. 155 



2. View showing rail case and installation of nonmetallic minerals in gallery 



of southwest court of U. S. National Museum. Looking north 155 



3. Views in graphite mine near Hague, Warren County, New York. From 



photographs by C. D. Walcott 1"0 



4. Section of the salt deposits at Stassfurt. From the Transactions of the 



Edinburg Geological Society, V, 1884, p. Ill 204 



5. Views of brine-evaporating tanks at Syracuse, New York. From photo- 



graphs by I. P. Bishop 210 



6. View of Tripoli mines in Carthage, Missouri 218 



7. Deposit of diatomaceous earth, Great Bend of Pitt River, Shasta County, 



California. From a photograph by J. S. Diller 218 



8. Map showing distribution of corundum and peridotite in the eastern 



United States. After J. V. Lewis, Bulletin II, North Carolina Geolog- 

 ical Survey 222 



9. Microstructure of emery. After Tschermak, Mineralogische und Petro- 



graphische Mittheilungen XIV, Part 4 224 



10. Section showing the formation of manganese deposits from decay of lime- 



stone. After Penrose, Annual Report Geological Survey of Arkansas, 



I, 1890 252 



11. Botryoidal psilomelane, Crimora, Virginia. Specimen No. 66722, U.S.N.M . 255 



12. Views showing occurrence of Calcite in Iceland. After Thoroddsen 259 



13. View in a cement quarry near Whitehall, Ulster County, New York. 



From a photograph by N. H. Darton 268 



14. View in a soapstone quarry, Lafayette, Pennsylvania 319 



15. Microsections showing the appearance of (1) kaolinite and (2) washed 



kaolin 330 



16. Microsections showing the appearance of (1) halloysite and (2) leda clay. 331 



17. Microsections showing the appearance of (1) Albany County, Wyoming, 



clay and (2) fuller's earth 332 



XI 



